Phenotypic traits are usually correlated with the environment where organism occurs. In this study, the distribution of Eremias velox in the eastern periphery of its range was specified, and its morphological variatio...Phenotypic traits are usually correlated with the environment where organism occurs. In this study, the distribution of Eremias velox in the eastern periphery of its range was specified, and its morphological variation was analyzed. Linear dimensions, pholidosis, coloration and pattern features were compared among 135 specimens from nine populations inhabiting the Balkhash, Ili and Alakol basins, Junggar and Turpan depressions in the territory of Southeast Kazakhstan and Xinjiang, Northwest China. The populations from the Junggar Depression(Kuytun, Shihezi and Urumqi) were characterized by higher mean values of linear characters, the number of scales across the middle of the body and gular, and were similar in the dominant coloration patterns. Small size, dark coloration and almost complete dominance of the striped-type coloration pattern among the specimens from the Alakol Lake islands seem to have an adaptive significance associated with the isolation of the population and type of their habitats. The subspecies Eremias velox roborowskii(endemic to the Turpan Depression) is elevated to species level, as supported by morphological divergence congruent with molecular and geographical data, including its peculiar type of coloration pattern, significantly lower amount of femoral pores and a higher percentage of specimens with one enlarged preanal scale(72.7%). These results together confirm a high degree of variability in morphology for E.veloх in the eastern periphery of its range, reflecting a complex orography and the existence of multiple geographical barriers in this territory.展开更多
<span style="font-family:Verdana;">The sequence of the ribosomal RNA gene (rDNA) plays an important role in species identification and phylogenetic analysis. However, the only published </span>&l...<span style="font-family:Verdana;">The sequence of the ribosomal RNA gene (rDNA) plays an important role in species identification and phylogenetic analysis. However, the only published </span><span><span style="font-family:Verdana;">full-length sequence of a ribosomal gene of green algae is that of </span><i><span style="font-family:Verdana;">Ulva mutabilis</span></i><span style="font-family:Verdana;">.</span></span><span style="font-family:Verdana;"> In this study, we </span><a name="_Hlk17805857"></a><span style="font-family:Verdana;">amplified the full-length sequence of each ribosomal gene unit of the ribosomal gene of </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;">. The full-length sequence of the ribosomal gene in </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;"> is 8676 bp, including the 1759 bp 18S rDNA, 576 bp internal transcribed spacer (ITS) + 5.8S rDNA, 3282 bp 28S </span><span style="font-family:Verdana;">rDNA, and 3059 bp intergenic spacer (IGS) region. We then carried out a series</span><span style="font-family:Verdana;"> of genetic analyses based on the ITS and IGS sequences, to verify whether IGS </span><span><span style="font-family:Verdana;">sequences are useful for studying the genetic diversity of green algae from different locations. We amplified the IGS sequences of </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;"> from 10 different locations in the Yellow Sea. Multiple alignments of the IGS sequences </span></span><span style="font-family:Verdana;">of samples from these 10 different sites revealed varying degrees of base </span><span><span style="font-family:Verdana;">differences, and comparative analysis of the ITS sequences revealed that our amplified species was classified as </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;"> and distinct from other green algae. In conclusion, our full-length amplified ribosomal gene provides useful information to enrich the data on green algae ribosomal genes and provides an effective mo</span></span><span style="font-family:Verdana;">lecular marker for the analysis of the interspecies and intraspecies relationships of </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;">.</span>展开更多
The mitochondrial genome is a prominent research topic due to its indispensable role in organisms and its application in many research disciplines.However,few studies have investigated intraspecies mitogenomic variati...The mitochondrial genome is a prominent research topic due to its indispensable role in organisms and its application in many research disciplines.However,few studies have investigated intraspecies mitogenomic variation.In this study,69 mitogenomes of the Black-throated Tit(Aegithalos concinnus)were assembled and annotated from a large number of short reads generated using high-throughput sequencing technology.Comparative analyses revealed that mitogenomic characteristics such as length,gene and nucleotide composition,codon usage,and duplicated control regions were relatively conserved despite substantial intraspecies morphological changes.Yet,all the individuals from the subspecies A.c.iredalei had one more nucleotide in the 12S rRNA than the other studied subspecies.Phylogenetic analyses showed five distinct lineages based on the complete mitogenomes and the 13 combined protein-coding genes,whereas only four lineages were observed when using the duplicate control regions.Most interestingly,each lineage had both copies of the control regions of the comprising individuals,indicating that the paralogous control regions were more similar than the orthologous sequences from the distinct lineages.This suggested the control regions had undergone concerted evolution.The Black-throated Tit has complex evolutionary history and needs further investigating the taxonomic status of these lineages,as well as the underlying evolutionary processes.Our findings call for more research on intraspecies mitogenomic variation.展开更多
Interspecies chimera through blastocyst complementation could be an alternative approach to create human organs in animals by using human pluripotent stem cells.A mismatch of the major histocompatibility complex of va...Interspecies chimera through blastocyst complementation could be an alternative approach to create human organs in animals by using human pluripotent stem cells.A mismatch of the major histocompatibility complex of vascular endothelial cells between the human and host animal will cause graft rejection in the transplanted organs.Therefore,to achieve a transplantable organ in animals without rejection,creation of vascular endothelial cells derived from humans within the organ is necessary.In this study,to explore whether donor xeno-pluripotent stem cells can compensate for blood vasculature in host animals,we generated rat-mouse chimeras by injection of rat embryonic stem cells(rESCs)into mouse blastocysts with deficiency of Flk-1 protein,which is associated with endothelial and hematopoietic cell development.We found that rESCs could differentiate into vascular endothelial and hematopoietic cells in the rat-mouse chimeras.The whole yolk sac(YS)of Flk-1^EGFP/ECFP rat-mouse chimera was full of rat blood vasculature.Rat genes related to vascular endothelial cells,arteries,and veins,blood vessels formation process,as well as hematopoietic cells,were highly expressed in the YS.Our results suggested that rat vascular endothelial cells could undergo proliferation,migration,and self-assembly to form blood vasculature and that hematopoietic cells could differentiate into B cells,T cells,and myeloid cells in rat-mouse chimeras,which was able to rescue early embryonic lethality caused by Flk-1 deficiency in mouse.展开更多
Geographic variability in vocalizations has been documented in many mammalian species. We examined to what extent it applies to the alarm calls of the European ground squirrel Spermophilus citellus. We recorded the ca...Geographic variability in vocalizations has been documented in many mammalian species. We examined to what extent it applies to the alarm calls of the European ground squirrel Spermophilus citellus. We recorded the calls of 82 adult individuals from 5 natural colonies in the Czech Republic and 24 adult individuals from an artificial seminatural colony located in a Czech zoo. The founders of this colony originated from 4 different natural colonies in the Czech Republic. Our results showed that there are hardly any differences in the acoustic structure of the alarm calls between male and female European ground squirrels. Discriminant function analysis showed the highest degree of discriminability for the most isolated sites (54-74% of individuals classified correctly), whereas the lowest degree of discriminability was found for 2 interconnected colonies (38-40% individuals classified correctly). Individuals from the artificial seminatural colony were often classified correctly to this colony (58% classified correctly);however, the precision of the classification was comparatively relatively low, that is, many individuals from other colonies were incorrectly classified into this seminatural colony. This likely corresponds to the different origins of its founders. These findings indicate that there is a rather substantial geographic variability in the alarm calls of the European ground squirrel, and our study highlights its possible impact on conservation measures such as establishing artificial colonies or reintroductions.展开更多
Even though vaccines against rabies are available,rabies still remains a burden killing a significant number of humans as well as domestic and wild animals in many parts of the world,including Nepal.In this study,we d...Even though vaccines against rabies are available,rabies still remains a burden killing a significant number of humans as well as domestic and wild animals in many parts of the world,including Nepal.In this study,we develop a mathematical model to describe transmission dynamics of rabies in Nepal.In particular,an indirect interspecies transmission from jackals to humans through dogs,which is relevant to the context of Nepal,is one of the novel features of our model.Our model utilizes annual dog-bite data collected from Nepal for a decade long period,allowing us to reasonably estimate parameters related to rabies transmission in Nepal.Using our model,we calculated the basic reproduction number(R_(0)=1:16)as well as intraspecies basic reproduction numbers of dogs(R_(0)^(D)=1:14)and jackals(R_(0)^(J)=0:07)for Nepal,and identified that the dog-related parameters are primary contributors to R0.Our results show that,along with dogs,jackals may also play an important role,albeit lesser extent,in the persistence of rabies in Nepal.Our model also suggests that control strategies may help reduce the prevalence significantly but the jackal vaccination may not be as effective as dog-related preventive strategies.To get deeper insight into the role of intraspecies and interspecies transmission between dog and jackal populations in the persistence of rabies,we also extended our model analysis into a wider parameter range.Interestingly,for some feasible parameters,even though rabies is theoretically controlled in each dog and jackal populations(R_(0)^(D)<1,R_(0)^(J)<1)if isolated,the rabies epidemic may still occur(R_(0)>1)due to interspecies transmission.These results may be useful to design effective prevention and control strategies for mitigating rabies burden in Nepal and other parts of the world.展开更多
基金supported by the Ministry of Education and Sciences of Kazakhstan (Grant No. 1850/GF4)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDPA20050201)+1 种基金the Ministry of Science and Technology of the People’s Republic of China (Grant No. 2015DFR30790)the National Natural Science Foundation of China (Grant No. 31672270)
文摘Phenotypic traits are usually correlated with the environment where organism occurs. In this study, the distribution of Eremias velox in the eastern periphery of its range was specified, and its morphological variation was analyzed. Linear dimensions, pholidosis, coloration and pattern features were compared among 135 specimens from nine populations inhabiting the Balkhash, Ili and Alakol basins, Junggar and Turpan depressions in the territory of Southeast Kazakhstan and Xinjiang, Northwest China. The populations from the Junggar Depression(Kuytun, Shihezi and Urumqi) were characterized by higher mean values of linear characters, the number of scales across the middle of the body and gular, and were similar in the dominant coloration patterns. Small size, dark coloration and almost complete dominance of the striped-type coloration pattern among the specimens from the Alakol Lake islands seem to have an adaptive significance associated with the isolation of the population and type of their habitats. The subspecies Eremias velox roborowskii(endemic to the Turpan Depression) is elevated to species level, as supported by morphological divergence congruent with molecular and geographical data, including its peculiar type of coloration pattern, significantly lower amount of femoral pores and a higher percentage of specimens with one enlarged preanal scale(72.7%). These results together confirm a high degree of variability in morphology for E.veloх in the eastern periphery of its range, reflecting a complex orography and the existence of multiple geographical barriers in this territory.
文摘<span style="font-family:Verdana;">The sequence of the ribosomal RNA gene (rDNA) plays an important role in species identification and phylogenetic analysis. However, the only published </span><span><span style="font-family:Verdana;">full-length sequence of a ribosomal gene of green algae is that of </span><i><span style="font-family:Verdana;">Ulva mutabilis</span></i><span style="font-family:Verdana;">.</span></span><span style="font-family:Verdana;"> In this study, we </span><a name="_Hlk17805857"></a><span style="font-family:Verdana;">amplified the full-length sequence of each ribosomal gene unit of the ribosomal gene of </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;">. The full-length sequence of the ribosomal gene in </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;"> is 8676 bp, including the 1759 bp 18S rDNA, 576 bp internal transcribed spacer (ITS) + 5.8S rDNA, 3282 bp 28S </span><span style="font-family:Verdana;">rDNA, and 3059 bp intergenic spacer (IGS) region. We then carried out a series</span><span style="font-family:Verdana;"> of genetic analyses based on the ITS and IGS sequences, to verify whether IGS </span><span><span style="font-family:Verdana;">sequences are useful for studying the genetic diversity of green algae from different locations. We amplified the IGS sequences of </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;"> from 10 different locations in the Yellow Sea. Multiple alignments of the IGS sequences </span></span><span style="font-family:Verdana;">of samples from these 10 different sites revealed varying degrees of base </span><span><span style="font-family:Verdana;">differences, and comparative analysis of the ITS sequences revealed that our amplified species was classified as </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;"> and distinct from other green algae. In conclusion, our full-length amplified ribosomal gene provides useful information to enrich the data on green algae ribosomal genes and provides an effective mo</span></span><span style="font-family:Verdana;">lecular marker for the analysis of the interspecies and intraspecies relationships of </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;">.</span>
基金financially supported by the National Natural Science Foundation of China(Grant No.32060310)a grant from the Department of Education of Guangxi.
文摘The mitochondrial genome is a prominent research topic due to its indispensable role in organisms and its application in many research disciplines.However,few studies have investigated intraspecies mitogenomic variation.In this study,69 mitogenomes of the Black-throated Tit(Aegithalos concinnus)were assembled and annotated from a large number of short reads generated using high-throughput sequencing technology.Comparative analyses revealed that mitogenomic characteristics such as length,gene and nucleotide composition,codon usage,and duplicated control regions were relatively conserved despite substantial intraspecies morphological changes.Yet,all the individuals from the subspecies A.c.iredalei had one more nucleotide in the 12S rRNA than the other studied subspecies.Phylogenetic analyses showed five distinct lineages based on the complete mitogenomes and the 13 combined protein-coding genes,whereas only four lineages were observed when using the duplicate control regions.Most interestingly,each lineage had both copies of the control regions of the comprising individuals,indicating that the paralogous control regions were more similar than the orthologous sequences from the distinct lineages.This suggested the control regions had undergone concerted evolution.The Black-throated Tit has complex evolutionary history and needs further investigating the taxonomic status of these lineages,as well as the underlying evolutionary processes.Our findings call for more research on intraspecies mitogenomic variation.
基金financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA16030503)National Key Research and Development Program of China(2017YFA0105103)+5 种基金Key Research&Development Program of Guangzhou Regenerative Medicine and Health Guangdong Laboratory(2018GZR110104004)Science and Technology Planning Project of Guangdong Province,China(2014A030312001,2017B020231001,2017A050501059,2017B030314056)Science and Technology Program of Guangzhou,China(201704030034)Research Unit of Generation of Large Animal Disease Models,Chinese Academy of Medical Sciences(2019-I2M-5-025)the Science and Technology Planning Project of Jiangmen(2017TD02)the Young People Fund of Wuyi University(2019TD05)。
文摘Interspecies chimera through blastocyst complementation could be an alternative approach to create human organs in animals by using human pluripotent stem cells.A mismatch of the major histocompatibility complex of vascular endothelial cells between the human and host animal will cause graft rejection in the transplanted organs.Therefore,to achieve a transplantable organ in animals without rejection,creation of vascular endothelial cells derived from humans within the organ is necessary.In this study,to explore whether donor xeno-pluripotent stem cells can compensate for blood vasculature in host animals,we generated rat-mouse chimeras by injection of rat embryonic stem cells(rESCs)into mouse blastocysts with deficiency of Flk-1 protein,which is associated with endothelial and hematopoietic cell development.We found that rESCs could differentiate into vascular endothelial and hematopoietic cells in the rat-mouse chimeras.The whole yolk sac(YS)of Flk-1^EGFP/ECFP rat-mouse chimera was full of rat blood vasculature.Rat genes related to vascular endothelial cells,arteries,and veins,blood vessels formation process,as well as hematopoietic cells,were highly expressed in the YS.Our results suggested that rat vascular endothelial cells could undergo proliferation,migration,and self-assembly to form blood vasculature and that hematopoietic cells could differentiate into B cells,T cells,and myeloid cells in rat-mouse chimeras,which was able to rescue early embryonic lethality caused by Flk-1 deficiency in mouse.
基金the Ministry of the Environment of the Czech Republic(project no.SP/2d4/61/08).
文摘Geographic variability in vocalizations has been documented in many mammalian species. We examined to what extent it applies to the alarm calls of the European ground squirrel Spermophilus citellus. We recorded the calls of 82 adult individuals from 5 natural colonies in the Czech Republic and 24 adult individuals from an artificial seminatural colony located in a Czech zoo. The founders of this colony originated from 4 different natural colonies in the Czech Republic. Our results showed that there are hardly any differences in the acoustic structure of the alarm calls between male and female European ground squirrels. Discriminant function analysis showed the highest degree of discriminability for the most isolated sites (54-74% of individuals classified correctly), whereas the lowest degree of discriminability was found for 2 interconnected colonies (38-40% individuals classified correctly). Individuals from the artificial seminatural colony were often classified correctly to this colony (58% classified correctly);however, the precision of the classification was comparatively relatively low, that is, many individuals from other colonies were incorrectly classified into this seminatural colony. This likely corresponds to the different origins of its founders. These findings indicate that there is a rather substantial geographic variability in the alarm calls of the European ground squirrel, and our study highlights its possible impact on conservation measures such as establishing artificial colonies or reintroductions.
基金The work of NKV was partially supported by NSF grants DMS-1951793,DMS-1616299,DMS-1836647,and DEB-2030479 from the National Science Foundation of USA,and the UGP award and the start-up fund from San Diego State University.
文摘Even though vaccines against rabies are available,rabies still remains a burden killing a significant number of humans as well as domestic and wild animals in many parts of the world,including Nepal.In this study,we develop a mathematical model to describe transmission dynamics of rabies in Nepal.In particular,an indirect interspecies transmission from jackals to humans through dogs,which is relevant to the context of Nepal,is one of the novel features of our model.Our model utilizes annual dog-bite data collected from Nepal for a decade long period,allowing us to reasonably estimate parameters related to rabies transmission in Nepal.Using our model,we calculated the basic reproduction number(R_(0)=1:16)as well as intraspecies basic reproduction numbers of dogs(R_(0)^(D)=1:14)and jackals(R_(0)^(J)=0:07)for Nepal,and identified that the dog-related parameters are primary contributors to R0.Our results show that,along with dogs,jackals may also play an important role,albeit lesser extent,in the persistence of rabies in Nepal.Our model also suggests that control strategies may help reduce the prevalence significantly but the jackal vaccination may not be as effective as dog-related preventive strategies.To get deeper insight into the role of intraspecies and interspecies transmission between dog and jackal populations in the persistence of rabies,we also extended our model analysis into a wider parameter range.Interestingly,for some feasible parameters,even though rabies is theoretically controlled in each dog and jackal populations(R_(0)^(D)<1,R_(0)^(J)<1)if isolated,the rabies epidemic may still occur(R_(0)>1)due to interspecies transmission.These results may be useful to design effective prevention and control strategies for mitigating rabies burden in Nepal and other parts of the world.