Pikas(Lagomorpha: Ochotonidae) are small mouselike lagomorphs. To investigate their adaptation to different ecological environments during their dispersal from the Qinghai-Xizang(Tibet) Plateau(QTP), we collected 226 ...Pikas(Lagomorpha: Ochotonidae) are small mouselike lagomorphs. To investigate their adaptation to different ecological environments during their dispersal from the Qinghai-Xizang(Tibet) Plateau(QTP), we collected 226 pikas and measured 20 morphological characteristics and recorded habitat information. We also sequenced the genome of 81specimens, representing 27 putative pika species.The genome-wide tree based on 4?090 coding genes identified five subgenera, i.e., Alienauroa, Conothoa,Lagotona, Ochotona, and Pika, consistent with morphometric data. Morphologically, Alienauroa and Ochotona had similar traits, including smaller size and earlier divergence time compared to other pikas.Consistently, the habitats of Alienauroa and Ochotona differed from those of the remaining subgenera. Phylogenetic signal analysis detected 83 genes significantly related to morphological characteristics, including several visual and hearingrelated genes. Analysis of shared amino acid substitutions and positively selected genes(PSGs) in Alienauroa and Ochotona identified two genes, i.e.,mitochondrial function-related TSFM(p.Q155E) and low-light visual sensitivity-related PROM1(p.H419Y).Functional experiments demonstrated that TSFM-155E significantly enhanced mitochondrial function compared to TSFM-155Q in other pikas, and PROM1-419Y decreased the modeling of dynamic intracellular chloride efflux upon calcium uptake. Alienauroa and Ochotona individuals mostly inhabit different environments(e.g., subtropical forests) than other pikas, suggesting that a shift from the larger ancestral type and changes in sensory acuity and energy enhancement may have been required in their new environments. This study increases our understanding of the evolutionary history of pikas.展开更多
Bare patches in alpine meadow are the main manifestation of its degradation.The change of bare patches in an alpine meadow in the Yellow River Source Zone during 2018-2019 was studied in relation to the disturbances c...Bare patches in alpine meadow are the main manifestation of its degradation.The change of bare patches in an alpine meadow in the Yellow River Source Zone during 2018-2019 was studied in relation to the disturbances caused by plateau pika(Ochotona curzoniae)population and simulated grazing via artificial mowing both independently and interactively.The disturbance was set at three levels of high,medium and no disturbance(control group).Bare patches were mapped by from unmanned aerial vehicle(UAV)images with fine resolution of 1 cm obtained in August 2018 and August 2019 in ArcGIS.The results showed that the total area of bare patches decreased by 112.05 m2 in sub-plots devoid of pika disturbance but increased by 126.37 m2 in other subplots.The highest rate of increase is 89.02%.The individual effect of pika exceeds the joint effect of pika and mowing disturbances.The sole effect of mowing is lower than the joint effect of pika disturbance and intensive mowing,but higher than the joint influence of pika disturbance and moderate mowing.Strong pika disturbance(14 per sub-plot)caused the influence of mowing from moderate to intensive to increase by five-fold.The area of bare patches treated with moderate mowing and no pika disturbance decreased at the highest pace(-37.22%).Intensive mowing and medium density pikas(100 pikas/ha)are considered the thresholds at which the bare patches start to expand.Even if the meadow is mowed at the medium and high intensity,the area of bare patches can be significantly reduced if plateau pika population is controlled to a low level.ANOVA analysis and longterm macro-scale satellite-derived results reveal that pika disturbance is more important in causing the bare patches to change than simulated grazing.Therefore,it is more important to control the number of pikas than to reduce grazing intensity to prevent the expansion of bare patches in the degraded alpine meadow in the study area.展开更多
[ Objective] To express lactate dehydrogenase C (LDH-C) gene in prokaryotic system and then purify the recombinant protein. E Meth- od] The LDI-I-C gene was amplified from black-lipped pika( Ochotona curzoniae) by...[ Objective] To express lactate dehydrogenase C (LDH-C) gene in prokaryotic system and then purify the recombinant protein. E Meth- od] The LDI-I-C gene was amplified from black-lipped pika( Ochotona curzoniae) by RT-PCR and ligated to the expression vector pET-32a. The E. coli BL21 (DE3) carrying the LDI-I-C gene was obtained and induced by IPTG (isopropy-beta-D-thiogalactoside). The expression products were analyzed by SDS-PAGE and purified by affinity chromatography. L Result] An approximately 1.0 kbp band appeared in the RT-PCR products as the- oretically expected. As evidenced by PCR and double enzyme digestion, an approximately 1.0 kbp fragment appeared, which indicated successful construction of expression vector. As analyzed by SDS-PAGE, a fusion protein with molecular weight slightly larger than 45 kDa was expressed in form of inclusion body. And very pure fusion protein was obtained by nickel ions-charged affinity chromatography. [ Coaclusion] The LDH-C gene of black-lipped pika has been cloned and expressed in E. coil展开更多
To determine the influence of the fence on plateau pika (<em>Ochotona curzoniae</em>), we measured the body mass, breeding status, population densities, using live-trapping and line-transect sampling in Ap...To determine the influence of the fence on plateau pika (<em>Ochotona curzoniae</em>), we measured the body mass, breeding status, population densities, using live-trapping and line-transect sampling in April and September 2006. In April, body mass of both male and female plateau pika inside of fence were significant higher than that outside of fence (♀: F = 6.583, <em>df</em> = 1.20, <em>p</em> = 0.019;♂: F = 6.49, <em>df</em> = 1.17, <em>p</em> = 0.021). The ratio of spermary drop of an adult male was also higher (92.31% vs 57.14%). In September, body mass of adult male in both study sites showed no significant difference (F = 0.001, <em>df</em> = 1.23, <em>p</em> = 0.975), but were all significant higher than that of April (F = 121.713, <em>df</em> = 1.22, <em>p</em> < 0.001;F = 105.819, <em>df</em> = 1.20, <em>p</em> < 0.001). In April, the population densities of both study sites showed on significant difference (F = 2.388, <em>df</em> = 1.38, <em>p</em> = 0.131), but the population density inside of fence was much higher than that outside of fence (F = 7.534, <em>df</em> = 1.38, <em>p</em> = 0.009) in September. Our results show that the changes of quality and quantity of food that available to plateau pika in winter, can depress the range of reducing body mass of plateau pika, make breeding season ahead, and then promote the increase of population.展开更多
Soon a furry-faced head with bright eyes and rounded ears will pop up and peer out.You are meeting the plateau pika. Its Tibetan name is abra and its scientific name Ochotona curzoniae.
This paper evaluated the impacts of mounds created by the plateau pika (Ochotona curzoniae) on the vege- tation composition, structure, and species diversity of an alpine Kobresia steppe meadow in Nagqu County, Tibet ...This paper evaluated the impacts of mounds created by the plateau pika (Ochotona curzoniae) on the vege- tation composition, structure, and species diversity of an alpine Kobresia steppe meadow in Nagqu County, Tibet Autonomous Region, China. Based on mound height or the depth of erosion pit, we defined five stages of erosion and compared the floristic features of communities at these stages with those in undisturbed sites. In the study area, the mounds and pits covered up to 7% of the total area. Lancea tibetica, Lamiophlomis rotata, and Potentilla bifurca were the dominant species in erosion pits, and Kobresia pygmaea, the dominant species in undisturbed sites, became a com- panion species in eroded areas. In the process of erosion, the original vegetation was covered by soil ejected by the pika, then the mounds were gradually eroded by wind and rain, and finally erosion pits formed. The vegetation coverage in- creased with increasing erosion stages but remained significantly lower than that in undisturbed sites. Improved coverage eventually reduced soil erosion, and pit depth eventually stabilized at around 20cm. Aboveground biomass increased with increasing erosion stage, but the proportion of low-quality forage reached more than 94%. The richness index and Shannon-Wiener index increased significantly with increasing erosion stage, but the richness index in mound and pit areas was significantly lower than that in undisturbed sites.展开更多
Severe Acute Respiratory Syndrome(SARS) is a deadly infectious disease caused by SARS Coronavirus(SARS-CoV).Inactivated SARS-CoV has been explored as a vaccine against SARS-CoV.However,safe and potent adjuvants,especi...Severe Acute Respiratory Syndrome(SARS) is a deadly infectious disease caused by SARS Coronavirus(SARS-CoV).Inactivated SARS-CoV has been explored as a vaccine against SARS-CoV.However,safe and potent adjuvants,especially with more efficient and economical needle-free vaccination are always needed more urgently in a pandemic.The development of a safe and effective mucosal adjuvant and vaccine for prevention of emergent infectious diseases such as SARS will be an important advancement.PIKA,a stabilized derivative of Poly(I:C),was previously reported to be safe and potent as adjuvant in mouse models.In the present study,we demonstrated that the intraperitoneal and intranasal co-administration of inactivated SARS-CoV vaccine together with this improved Poly(I:C) derivative induced strong anti-SARS-CoV mucosal and systemic humoral immune responses with neutralizing activity against pseudotyped virus.Although intraperitoneal immunization of inactivated SARS-CoV vaccine alone could induce a certain level of neutralizing activity in serum as well as in mucosal sites,co-administration of inactivated SARS-CoV vaccine with PIKA as adjuvant could induce a much higher neutralizing activity.When intranasal immunization was used,PIKA was obligatorily for inducing neutralizing activity in serum as well as in mucosal sites and was correlated with both mucosal IgA and mucosal IgG response.Overall,PIKA could be a good mucosal adjuvant candidate for inactivated SARS-CoV vaccine for use in possible future pandemic.展开更多
The harsh environment in the Tibetan plateau,the highest place in the world,poses thermoregulatory challenges and hypoxic stress to animals.The impacts of plateau environment on animal physiology and reproduction incl...The harsh environment in the Tibetan plateau,the highest place in the world,poses thermoregulatory challenges and hypoxic stress to animals.The impacts of plateau environment on animal physiology and reproduction include external factors such as strong ultraviolet radiation and low temperature,and internal factors such as animal metabolites and gut microbiota.However,it remains unclear how plateau pika adapt to high altitudes through the combination of serum metabolites and gut microbiota.To this end,we captured 24 wild plateau pikas at the altitudes of 3400,3600,or 3800 m a.s.l.in a Tibetan alpine grassland.Using the machine learning algorithms(random forest),we identified five biomarkers of serum metabolites indicative of the altitudes,that is,dihydrotestosterone,homo-l-arginine,alpha-ketoglutaric-acid,serotonin,and threonine,which were related to body weight,reproduction,and energy metabolism of pika.Those metabolic biomarkers were positively correlated with Lachnospiraceae_Agathobacter,Ruminococcaceae,or Prevotellaceae_Prevotella,suggesting the close relationship between metabolites and gut microbiota.By identifying the metabolic biomarkers and gut microbiota analysis,we reveal the mechanisms of adaptation to high altitudes in plateau pika.展开更多
Human disturbance,particularly road traffic,is one of the greatest threats to wildlife.Considering the association between alerting behavior and the survival of animals,it is important to study the effects of road tra...Human disturbance,particularly road traffic,is one of the greatest threats to wildlife.Considering the association between alerting behavior and the survival of animals,it is important to study the effects of road traffic on alerting behavior of wildlife.Previous studies assessing the shortterm impact of road traffic on alerting behavior of wildlife have focused on vigilance distances.However,studies on the use of alarm calls are scarce,and it is unclear whether such behavioral responses change after repeated exposure to road traffic.We assessed the alerting behavior of plateau pikas(Ochotona curzoniae)who were near or far from roads when facing a potential predator.We found that pikas near roads exhibited shorter vigilance and tolerance distances,and produced fewer alarm calls than those relatively far away from roads.Furthermore,both vigilance and tolerance distances of plateau pikas were significantly positively correlated with the distance from the burrow to the road.Road traffic reduced antipredator responses and shaped alerting behavior;that is,pikas near roads were bolder and more silent compared to those far away from roads.Our findings suggest that increasing urbanization will have corresponding effects on animal behavior,which may have significant fitness effects in the future.展开更多
Emerging and re-emerging viruses from wild animals have seriously threatened the health of humans and domesticated animals in recent years.Herein,we isolated a new mammalian orthoreovirus(MRV),Pika/MRV/GCCDC7/2019(PMR...Emerging and re-emerging viruses from wild animals have seriously threatened the health of humans and domesticated animals in recent years.Herein,we isolated a new mammalian orthoreovirus(MRV),Pika/MRV/GCCDC7/2019(PMRV-GCCDC7),in the Qinghai-Tibet Plateau wild pika(Ochotona curzoniae).Though the PMRVGCCDC7 shows features of a typical reovirus with ten gene segments arranged in 3:3:4 in length,the virus belongs to an independent evolutionary branch compared to other MRVs based on phylogenetic tree analysis.The results of cellular susceptibility,species tropism,and replication kinetics of PMRV-GCCDC7 indicated the virus could infect four human cell lines(A549,Huh7,HCT,and LoVo)and six non-human cell lines,including Vero-E6,LLCMK2,BHK-21,N2a,MDCK,and RfKT cell,derived from diverse mammals,i.e.monkey,mice,canine and bat,which revealed the potential of PMRV-GCCDC7 to infect a variety of hosts.Infection of BALB/c mice with PMRVGCCDC7 via intranasal inoculation led to relative weight loss,lung tissue damage and inflammation with the increase of virus titer,but no serious respiratory symptoms and death occurred.The characterization of the new reovirus from a plateau-based wild animal has expanded our knowledge of the host range of MRV and provided insight into its risk of trans-species transmission and zoonotic diseases.展开更多
An adjuvant is usually used to enhance the immune response induced by vaccines. The choice of adjuvant or immune enhancer determines the effectiveness of the immune response. Currently, aluminium (Alum, a generic ter...An adjuvant is usually used to enhance the immune response induced by vaccines. The choice of adjuvant or immune enhancer determines the effectiveness of the immune response. Currently, aluminium (Alum, a generic term for salts of aluminium) is the only FDA-approved adjuvant. Alum predominantly induces the differentiation of Th2 cells and thus mediates an antibody immune response. Therefore, there is an urgent need for new adjuvants that enhance not only humoral but also cellular immune responses. In the present study, we demonstrates that PIKA (a stabilized dsRNA) as an adjuvant directly induces the activation and the proliferation of both B and NK cells in vitro. Injection of PIKA into mice results in the production of cytokines in vivo. In addition, the study demonstrates that PIKA promotes the maturation of bone marrow-derived dendritic cells (BMDCs) including up-regulation of the co-stimulatory molecules CD80, CD86 and CD40, and the induction of cytokines such as IL-12p70, IL-12p40 and IL-6. Importantly, after immunization of mice with HBsAg plus PIKA, the presence of PIKA enhances the titers of HBsAg-specific IgG and HBsAg-specific IFN-γ production. These results demonstrate that PIKA as an adjuvant can promote both humoral and cellular immune responses. These might have an implication in applying PIKA as an adjuvant to be used in the design and development of both therapeutic and preventive vaccines, and used in the clinical study.展开更多
Seasonal variations in gut microbiota of small mammals and how they are influenced by environmental variables are relatively poorly understood.We sampled 162 wild plateau pikas(Ochotona curzoniae)in 4 seasons over 2 a...Seasonal variations in gut microbiota of small mammals and how they are influenced by environmental variables are relatively poorly understood.We sampled 162 wild plateau pikas(Ochotona curzoniae)in 4 seasons over 2 and a half years and recorded the air temperature,precipitation,and nutrient content in edible vegetation at the sampling site.After conducting 16S rRNA and shotgun metagenomic sequencing,we found that the highest alpha diversity,the relative abundance of Firmicutes,and the simplest co-occurrence network occurred in winter,whereas the highest relative abundance of Proteobacteria and the most complex network structure were observed in spring.The highest relative abundance of Verrucomicrobiota and Spirochaetota was seen in summer and autumn,respectively.Air temperature,precipitation,and the contents of crude protein,crude fiber,and polysaccharide in vegetation had significant effects on the seasonal changes in gut microbiota.Diet contributed more to microbial variation than climatic factors.Metagenomic analysis revealed that the amino acid metabolism pathway and axillary activity enzymes were most abundant in summer,while abundance of carbohydrate-binding modules and carbohydrate esterases was highest in spring.These microbial variations were related to the changes in dietary nutrition,indicating that gut microbiota of plateau pika contribute to the efficient use of food resources.This study provides new evidence of how external environmental factors affect the intestinal environment of small mammals.展开更多
The plateau pika(Ochotona curzoniae)has been engaged in pest control for many years based on the logic that the plateau pika is responsible for alpine grassland degradation and competes with livestock for forage resou...The plateau pika(Ochotona curzoniae)has been engaged in pest control for many years based on the logic that the plateau pika is responsible for alpine grassland degradation and competes with livestock for forage resources.However,the plateau pika is an important species which has multiple benefits in Qinghai-Tibetan Plateau,as it(i)makes burrows that are the primary homes for lizards and a variety of small birds;(ii)creates microhabitat disturbance that promotes the increase of plant species richness;(iii)serves as the principal prey for almost all of the plateau predator species;and(iv)contributes positively to the dynamic equilibriumof alpine ecosystems.展开更多
Koslov’s pika,Ochotona koslowi(Büchner),was surveyed in western China.This endangered species is poorly known.We determined that it is a burrowing pika,and lives in social family groups at high densities.It prim...Koslov’s pika,Ochotona koslowi(Büchner),was surveyed in western China.This endangered species is poorly known.We determined that it is a burrowing pika,and lives in social family groups at high densities.It primarily occupies high-elevation cold grassland vegetation.It appears to have a high reproductive rate.More emphasis should be placed on research into this unique species in China.展开更多
The genus Ochotona(pikas)is a clade of cold-tolerant lagomorphs that includes many high-elevation species.Pikas offer a unique opportunity to study adaptations and potential limitations of an ecologically important ma...The genus Ochotona(pikas)is a clade of cold-tolerant lagomorphs that includes many high-elevation species.Pikas offer a unique opportunity to study adaptations and potential limitations of an ecologically important mammal to high-elevation hypoxia.We analyzed the evolution of 3 mitochondrial genes encoding the catalytic core of cytochrome c oxidase(COX)in 10 pika species occupying elevations from sea level to 5000 m.COX is an enzyme highly reliant on oxygen and essential for cell function.One amino acid property,the equilibrium constant(ionization of COOH),was found to be under selection in the overall protein complex.We observed a strong relationship between the net value change in this property and the elevation each species occupies,with higher-elevation species having potentially more efficient proteins.We also found evidence of selection in low-elevation species for potentially less efficient COX,perhaps trading efficiency for heat production in the absence of hypoxia.Our results suggest that different pika species may have evolved elevation-specific COX proteins,specialization that may indicate limitations in their ability to shift their elevational ranges in response to future climate change.展开更多
基金supported by the National Natural Science Foundation of China (31470110, 31970399)China National GeneBank (CNGB)。
文摘Pikas(Lagomorpha: Ochotonidae) are small mouselike lagomorphs. To investigate their adaptation to different ecological environments during their dispersal from the Qinghai-Xizang(Tibet) Plateau(QTP), we collected 226 pikas and measured 20 morphological characteristics and recorded habitat information. We also sequenced the genome of 81specimens, representing 27 putative pika species.The genome-wide tree based on 4?090 coding genes identified five subgenera, i.e., Alienauroa, Conothoa,Lagotona, Ochotona, and Pika, consistent with morphometric data. Morphologically, Alienauroa and Ochotona had similar traits, including smaller size and earlier divergence time compared to other pikas.Consistently, the habitats of Alienauroa and Ochotona differed from those of the remaining subgenera. Phylogenetic signal analysis detected 83 genes significantly related to morphological characteristics, including several visual and hearingrelated genes. Analysis of shared amino acid substitutions and positively selected genes(PSGs) in Alienauroa and Ochotona identified two genes, i.e.,mitochondrial function-related TSFM(p.Q155E) and low-light visual sensitivity-related PROM1(p.H419Y).Functional experiments demonstrated that TSFM-155E significantly enhanced mitochondrial function compared to TSFM-155Q in other pikas, and PROM1-419Y decreased the modeling of dynamic intracellular chloride efflux upon calcium uptake. Alienauroa and Ochotona individuals mostly inhabit different environments(e.g., subtropical forests) than other pikas, suggesting that a shift from the larger ancestral type and changes in sensory acuity and energy enhancement may have been required in their new environments. This study increases our understanding of the evolutionary history of pikas.
基金financially supported by the National Natural Science Foundation of China(Grant No.31872999)Project of the Science and Technology Department of Qinghai Province(Grant No.2018-ZJ781)+2 种基金Discipline Innovation and Introducing Talents Program of Higher Education Institutions(the 111 Project)(Grant No.D18013)Changjiang Scholars and Innovation Team Development plan(Grant No.IRT17R62)China Scholarship Council(Grant No.201907660003)。
文摘Bare patches in alpine meadow are the main manifestation of its degradation.The change of bare patches in an alpine meadow in the Yellow River Source Zone during 2018-2019 was studied in relation to the disturbances caused by plateau pika(Ochotona curzoniae)population and simulated grazing via artificial mowing both independently and interactively.The disturbance was set at three levels of high,medium and no disturbance(control group).Bare patches were mapped by from unmanned aerial vehicle(UAV)images with fine resolution of 1 cm obtained in August 2018 and August 2019 in ArcGIS.The results showed that the total area of bare patches decreased by 112.05 m2 in sub-plots devoid of pika disturbance but increased by 126.37 m2 in other subplots.The highest rate of increase is 89.02%.The individual effect of pika exceeds the joint effect of pika and mowing disturbances.The sole effect of mowing is lower than the joint effect of pika disturbance and intensive mowing,but higher than the joint influence of pika disturbance and moderate mowing.Strong pika disturbance(14 per sub-plot)caused the influence of mowing from moderate to intensive to increase by five-fold.The area of bare patches treated with moderate mowing and no pika disturbance decreased at the highest pace(-37.22%).Intensive mowing and medium density pikas(100 pikas/ha)are considered the thresholds at which the bare patches start to expand.Even if the meadow is mowed at the medium and high intensity,the area of bare patches can be significantly reduced if plateau pika population is controlled to a low level.ANOVA analysis and longterm macro-scale satellite-derived results reveal that pika disturbance is more important in causing the bare patches to change than simulated grazing.Therefore,it is more important to control the number of pikas than to reduce grazing intensity to prevent the expansion of bare patches in the degraded alpine meadow in the study area.
基金funded by the Applied Fundamental Study of Sichuan Province ( 2008JY0068)China Natural Science Foundation ( 31071700)Funds of the State Ethnic Affairs Commission of PRC ( 08XN04)
文摘[ Objective] To express lactate dehydrogenase C (LDH-C) gene in prokaryotic system and then purify the recombinant protein. E Meth- od] The LDI-I-C gene was amplified from black-lipped pika( Ochotona curzoniae) by RT-PCR and ligated to the expression vector pET-32a. The E. coli BL21 (DE3) carrying the LDI-I-C gene was obtained and induced by IPTG (isopropy-beta-D-thiogalactoside). The expression products were analyzed by SDS-PAGE and purified by affinity chromatography. L Result] An approximately 1.0 kbp band appeared in the RT-PCR products as the- oretically expected. As evidenced by PCR and double enzyme digestion, an approximately 1.0 kbp fragment appeared, which indicated successful construction of expression vector. As analyzed by SDS-PAGE, a fusion protein with molecular weight slightly larger than 45 kDa was expressed in form of inclusion body. And very pure fusion protein was obtained by nickel ions-charged affinity chromatography. [ Coaclusion] The LDH-C gene of black-lipped pika has been cloned and expressed in E. coil
文摘To determine the influence of the fence on plateau pika (<em>Ochotona curzoniae</em>), we measured the body mass, breeding status, population densities, using live-trapping and line-transect sampling in April and September 2006. In April, body mass of both male and female plateau pika inside of fence were significant higher than that outside of fence (♀: F = 6.583, <em>df</em> = 1.20, <em>p</em> = 0.019;♂: F = 6.49, <em>df</em> = 1.17, <em>p</em> = 0.021). The ratio of spermary drop of an adult male was also higher (92.31% vs 57.14%). In September, body mass of adult male in both study sites showed no significant difference (F = 0.001, <em>df</em> = 1.23, <em>p</em> = 0.975), but were all significant higher than that of April (F = 121.713, <em>df</em> = 1.22, <em>p</em> < 0.001;F = 105.819, <em>df</em> = 1.20, <em>p</em> < 0.001). In April, the population densities of both study sites showed on significant difference (F = 2.388, <em>df</em> = 1.38, <em>p</em> = 0.131), but the population density inside of fence was much higher than that outside of fence (F = 7.534, <em>df</em> = 1.38, <em>p</em> = 0.009) in September. Our results show that the changes of quality and quantity of food that available to plateau pika in winter, can depress the range of reducing body mass of plateau pika, make breeding season ahead, and then promote the increase of population.
文摘Soon a furry-faced head with bright eyes and rounded ears will pop up and peer out.You are meeting the plateau pika. Its Tibetan name is abra and its scientific name Ochotona curzoniae.
基金Under the auspices of the Science and Technology Committee of Tibet Autonomous Region (No. 200101046)
文摘This paper evaluated the impacts of mounds created by the plateau pika (Ochotona curzoniae) on the vege- tation composition, structure, and species diversity of an alpine Kobresia steppe meadow in Nagqu County, Tibet Autonomous Region, China. Based on mound height or the depth of erosion pit, we defined five stages of erosion and compared the floristic features of communities at these stages with those in undisturbed sites. In the study area, the mounds and pits covered up to 7% of the total area. Lancea tibetica, Lamiophlomis rotata, and Potentilla bifurca were the dominant species in erosion pits, and Kobresia pygmaea, the dominant species in undisturbed sites, became a com- panion species in eroded areas. In the process of erosion, the original vegetation was covered by soil ejected by the pika, then the mounds were gradually eroded by wind and rain, and finally erosion pits formed. The vegetation coverage in- creased with increasing erosion stages but remained significantly lower than that in undisturbed sites. Improved coverage eventually reduced soil erosion, and pit depth eventually stabilized at around 20cm. Aboveground biomass increased with increasing erosion stage, but the proportion of low-quality forage reached more than 94%. The richness index and Shannon-Wiener index increased significantly with increasing erosion stage, but the richness index in mound and pit areas was significantly lower than that in undisturbed sites.
基金supported by the National Natural Science Foundation of China (30670097)National Basic Research Program of China (973 Program) (2005CB522903)+1 种基金National Key R&D Program (2007BAI28B04)National S&T Major Project on Major Infectious Diseases (2008ZX10001-010)from the Ministry of Science and Technology of the People’s Republic of China
文摘Severe Acute Respiratory Syndrome(SARS) is a deadly infectious disease caused by SARS Coronavirus(SARS-CoV).Inactivated SARS-CoV has been explored as a vaccine against SARS-CoV.However,safe and potent adjuvants,especially with more efficient and economical needle-free vaccination are always needed more urgently in a pandemic.The development of a safe and effective mucosal adjuvant and vaccine for prevention of emergent infectious diseases such as SARS will be an important advancement.PIKA,a stabilized derivative of Poly(I:C),was previously reported to be safe and potent as adjuvant in mouse models.In the present study,we demonstrated that the intraperitoneal and intranasal co-administration of inactivated SARS-CoV vaccine together with this improved Poly(I:C) derivative induced strong anti-SARS-CoV mucosal and systemic humoral immune responses with neutralizing activity against pseudotyped virus.Although intraperitoneal immunization of inactivated SARS-CoV vaccine alone could induce a certain level of neutralizing activity in serum as well as in mucosal sites,co-administration of inactivated SARS-CoV vaccine with PIKA as adjuvant could induce a much higher neutralizing activity.When intranasal immunization was used,PIKA was obligatorily for inducing neutralizing activity in serum as well as in mucosal sites and was correlated with both mucosal IgA and mucosal IgG response.Overall,PIKA could be a good mucosal adjuvant candidate for inactivated SARS-CoV vaccine for use in possible future pandemic.
基金The authors are very grateful for the valuable comments on manuscript revisions of the editor.The authors are grateful to Metware Biotechnology Co.,Ltd for their contribution and assistance in Targeted 500 metabolomics analysis.This study was financially supported by the Leading Scientist Project of Qinghai Province(2023-NK-147)the Foundation of Science and Technology of Gansu Province(22JR5RA457)+4 种基金the Fundamental Research Funds for the Central Universities(lzujbky-2022-ct04)the National Natural Science Foundation of China(32061123004)the Open Fund Project of Guangxi Key Laboratory of Precision Medicine for Genetic Diseases(GXWCH-ZDKF-2022-15,Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region)the Open Fund Project of Guangxi Key Laboratory of Reproductive Health and Birth Defect Prevention(GXWCH-ZDKF-2022-09,Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region)the Foundation of Guangxi Health Commission(S2021068).
文摘The harsh environment in the Tibetan plateau,the highest place in the world,poses thermoregulatory challenges and hypoxic stress to animals.The impacts of plateau environment on animal physiology and reproduction include external factors such as strong ultraviolet radiation and low temperature,and internal factors such as animal metabolites and gut microbiota.However,it remains unclear how plateau pika adapt to high altitudes through the combination of serum metabolites and gut microbiota.To this end,we captured 24 wild plateau pikas at the altitudes of 3400,3600,or 3800 m a.s.l.in a Tibetan alpine grassland.Using the machine learning algorithms(random forest),we identified five biomarkers of serum metabolites indicative of the altitudes,that is,dihydrotestosterone,homo-l-arginine,alpha-ketoglutaric-acid,serotonin,and threonine,which were related to body weight,reproduction,and energy metabolism of pika.Those metabolic biomarkers were positively correlated with Lachnospiraceae_Agathobacter,Ruminococcaceae,or Prevotellaceae_Prevotella,suggesting the close relationship between metabolites and gut microbiota.By identifying the metabolic biomarkers and gut microbiota analysis,we reveal the mechanisms of adaptation to high altitudes in plateau pika.
基金supported by Sichuan Science and Technology Program(2022JDTD0026)National Natural Science Foundation of China(31772464,32001095)Youth Innovation Promotion Association CAS(2012274).
文摘Human disturbance,particularly road traffic,is one of the greatest threats to wildlife.Considering the association between alerting behavior and the survival of animals,it is important to study the effects of road traffic on alerting behavior of wildlife.Previous studies assessing the shortterm impact of road traffic on alerting behavior of wildlife have focused on vigilance distances.However,studies on the use of alarm calls are scarce,and it is unclear whether such behavioral responses change after repeated exposure to road traffic.We assessed the alerting behavior of plateau pikas(Ochotona curzoniae)who were near or far from roads when facing a potential predator.We found that pikas near roads exhibited shorter vigilance and tolerance distances,and produced fewer alarm calls than those relatively far away from roads.Furthermore,both vigilance and tolerance distances of plateau pikas were significantly positively correlated with the distance from the burrow to the road.Road traffic reduced antipredator responses and shaped alerting behavior;that is,pikas near roads were bolder and more silent compared to those far away from roads.Our findings suggest that increasing urbanization will have corresponding effects on animal behavior,which may have significant fitness effects in the future.
基金the National Key Research and Development Program of China(2021YFC0863400,2022YFC2604105).
文摘Emerging and re-emerging viruses from wild animals have seriously threatened the health of humans and domesticated animals in recent years.Herein,we isolated a new mammalian orthoreovirus(MRV),Pika/MRV/GCCDC7/2019(PMRV-GCCDC7),in the Qinghai-Tibet Plateau wild pika(Ochotona curzoniae).Though the PMRVGCCDC7 shows features of a typical reovirus with ten gene segments arranged in 3:3:4 in length,the virus belongs to an independent evolutionary branch compared to other MRVs based on phylogenetic tree analysis.The results of cellular susceptibility,species tropism,and replication kinetics of PMRV-GCCDC7 indicated the virus could infect four human cell lines(A549,Huh7,HCT,and LoVo)and six non-human cell lines,including Vero-E6,LLCMK2,BHK-21,N2a,MDCK,and RfKT cell,derived from diverse mammals,i.e.monkey,mice,canine and bat,which revealed the potential of PMRV-GCCDC7 to infect a variety of hosts.Infection of BALB/c mice with PMRVGCCDC7 via intranasal inoculation led to relative weight loss,lung tissue damage and inflammation with the increase of virus titer,but no serious respiratory symptoms and death occurred.The characterization of the new reovirus from a plateau-based wild animal has expanded our knowledge of the host range of MRV and provided insight into its risk of trans-species transmission and zoonotic diseases.
基金supported by Guangzhou Sciences and Technology Grant-2005 Project(2005Z1-E4014)Natural Key Science Foundation of Guangdong Province of China(04105349).
文摘An adjuvant is usually used to enhance the immune response induced by vaccines. The choice of adjuvant or immune enhancer determines the effectiveness of the immune response. Currently, aluminium (Alum, a generic term for salts of aluminium) is the only FDA-approved adjuvant. Alum predominantly induces the differentiation of Th2 cells and thus mediates an antibody immune response. Therefore, there is an urgent need for new adjuvants that enhance not only humoral but also cellular immune responses. In the present study, we demonstrates that PIKA (a stabilized dsRNA) as an adjuvant directly induces the activation and the proliferation of both B and NK cells in vitro. Injection of PIKA into mice results in the production of cytokines in vivo. In addition, the study demonstrates that PIKA promotes the maturation of bone marrow-derived dendritic cells (BMDCs) including up-regulation of the co-stimulatory molecules CD80, CD86 and CD40, and the induction of cytokines such as IL-12p70, IL-12p40 and IL-6. Importantly, after immunization of mice with HBsAg plus PIKA, the presence of PIKA enhances the titers of HBsAg-specific IgG and HBsAg-specific IFN-γ production. These results demonstrate that PIKA as an adjuvant can promote both humoral and cellular immune responses. These might have an implication in applying PIKA as an adjuvant to be used in the design and development of both therapeutic and preventive vaccines, and used in the clinical study.
基金supported by the Grant from CAS No.152111KYSB20160089Qinghai innovation platform construction project by Chinese Academy of Sciences(2021-ZJ-Y01)+2 种基金the project of western light for interdisciplinary teamScience and Technology Department of Qinghai Province Major Project“Sanjiangyaun National Park Animal Genome Program”the Natural Science Foundation of Qinghai Province(2019-ZJ-7024).
文摘Seasonal variations in gut microbiota of small mammals and how they are influenced by environmental variables are relatively poorly understood.We sampled 162 wild plateau pikas(Ochotona curzoniae)in 4 seasons over 2 and a half years and recorded the air temperature,precipitation,and nutrient content in edible vegetation at the sampling site.After conducting 16S rRNA and shotgun metagenomic sequencing,we found that the highest alpha diversity,the relative abundance of Firmicutes,and the simplest co-occurrence network occurred in winter,whereas the highest relative abundance of Proteobacteria and the most complex network structure were observed in spring.The highest relative abundance of Verrucomicrobiota and Spirochaetota was seen in summer and autumn,respectively.Air temperature,precipitation,and the contents of crude protein,crude fiber,and polysaccharide in vegetation had significant effects on the seasonal changes in gut microbiota.Diet contributed more to microbial variation than climatic factors.Metagenomic analysis revealed that the amino acid metabolism pathway and axillary activity enzymes were most abundant in summer,while abundance of carbohydrate-binding modules and carbohydrate esterases was highest in spring.These microbial variations were related to the changes in dietary nutrition,indicating that gut microbiota of plateau pika contribute to the efficient use of food resources.This study provides new evidence of how external environmental factors affect the intestinal environment of small mammals.
文摘The plateau pika(Ochotona curzoniae)has been engaged in pest control for many years based on the logic that the plateau pika is responsible for alpine grassland degradation and competes with livestock for forage resources.However,the plateau pika is an important species which has multiple benefits in Qinghai-Tibetan Plateau,as it(i)makes burrows that are the primary homes for lizards and a variety of small birds;(ii)creates microhabitat disturbance that promotes the increase of plant species richness;(iii)serves as the principal prey for almost all of the plateau predator species;and(iv)contributes positively to the dynamic equilibriumof alpine ecosystems.
文摘Koslov’s pika,Ochotona koslowi(Büchner),was surveyed in western China.This endangered species is poorly known.We determined that it is a burrowing pika,and lives in social family groups at high densities.It primarily occupies high-elevation cold grassland vegetation.It appears to have a high reproductive rate.More emphasis should be placed on research into this unique species in China.
文摘The genus Ochotona(pikas)is a clade of cold-tolerant lagomorphs that includes many high-elevation species.Pikas offer a unique opportunity to study adaptations and potential limitations of an ecologically important mammal to high-elevation hypoxia.We analyzed the evolution of 3 mitochondrial genes encoding the catalytic core of cytochrome c oxidase(COX)in 10 pika species occupying elevations from sea level to 5000 m.COX is an enzyme highly reliant on oxygen and essential for cell function.One amino acid property,the equilibrium constant(ionization of COOH),was found to be under selection in the overall protein complex.We observed a strong relationship between the net value change in this property and the elevation each species occupies,with higher-elevation species having potentially more efficient proteins.We also found evidence of selection in low-elevation species for potentially less efficient COX,perhaps trading efficiency for heat production in the absence of hypoxia.Our results suggest that different pika species may have evolved elevation-specific COX proteins,specialization that may indicate limitations in their ability to shift their elevational ranges in response to future climate change.