Drought-triggered repression of miR166 promotes drought tolerance in soybean

Drought stress limits agricultural productivity worldwide.Identifying and characterizing genetic components of drought stress-tolerance networks may improve crop resistance to drought stress.We show that the regulatory module formed by miR166 and its target gene,ATHB14-LIKE,functions in the regulation of drought tolerance in soybean(Glycine max).Drought stress represses the accumulation of miR166,leading to upregulation of its target genes.Optimal knockdown of miR166 in the stable transgenic line GmSTTM166 conferred drought tolerance without affecting yield.Expression of ABA signaling pathway genes was regulated by the miR166-mediated regulatory pathway,and ATHB14-LIKE directly activates some of these genes.There is a feedback regulation between ATHB14-LIKE and MIR166 genes,and ATHB14-LIKE inhibits MIR166 expression.These findings reveal that drought-triggered regulation of the miR166-mediated regulatory pathway increases plants drought resistance,providing new insights into drought stress regulatory network in soybean.

Generation of male-sterile soybean lines with the CRISPR/Cas9 system

Soybean [Glycine max(L.) Merr.] provides a rich source of plant protein and oil worldwide. The commercial use of transgenic technology in soybean has become a classical example of the application of biotechnology to crop improvement. Although genetically modified soybeans have achieved commercial success,hybrid soybean breeding is also a potential way to increase soybean yield. Soybean cytoplasmic malesterile(CMS) lines have been used in three-line hybrid breeding systems, but their application to exploiting soybean heterosis has been limited by rare germplasm resource of sterile lines. The generation of various genetic diversity male-sterile soybean lines will help to overcome the shortcoming. In this study,we used targeted editing of AMS homologs in soybean by CRISPR/Cas9 technology for the first time to generate stable male-sterile lines. Targeted editing of GmAMS1 resulted in a male-sterile phenotype,while editing of GmAMS2 failed to produce male-sterile lines. GmAMS1 functions not only in the formation of the pollen wall but also in the controlling the degradation of the soybean tapetum.CRISPR/Cas9 technology could be used to rapidly produce stable male-sterile lines, providing new sterile-line materials for soybean hybrid breeding systems.

Effect of B-Site Ordering on the Magnetic Order in Multifunctional La2NiMnO6 Double Perovskite

To obtain various Ni/Mn orderings,we use a low-temperature synthesized method to modulate the Ni/Mn ordering of the ferromagnetic-ferroelastic La2NiMnO6 compound,and the Ni/Mn ordering is estimated by the low-temperature saturation magnetism.The microstructures,crystal structures and magnetic properties are investigated,and the Landau theory are used to describe the form and magnitude of the coupling effects between Ni/Mn ordering and magnetic order parameters.It is predicted that the Ni/Mn ordering would be a strong coupling effect with the Curie transition temperatures if the La2NiMnO6 sample stoichiometry is close.

Efficacy and safety of ixekizumab in Chinese patients with plaque psoriasis

To the Editor:Psoriasis is a common,chronic papulosquamous skin disease occurring worldwide,presenting at any age,and leading to a substantial burden for individuals and society.Interleukin(IL)-17A is considered the key effector cytokine inducing psoriatic inflammation and tissue damage.[1]Ixekizumab is a humanized monoclonal immunoglobulin G specifically binding to and inhibiting IL-17A.The efficacy and safety of ixekizumab in patients with psoriasis have been clearly demonstrated in several randomized clinical trials,namely UNCOVER-1,UNCOVER-2,UNCOVER-3,and UNCOVER-J.[2,3]However,the clinical research data on ixekizumab in Chinese psoriasis patients remain limited.

Hysteresis in sap flow and its controlling mechanisms for a deciduous broad-leaved tree species in a humid karst region

The critical zone(CZ) represents the intersection of the biosphere with the atmosphere, hydrosphere and lithosphere.Understanding the hydrological processes and human impact factors on the CZ is fundamental to sustainable water resources management for agroforestry. Transpiration(T) is an important component of terrestrial evapotranspiration(ET), and understanding the time lag(TL) between vegetation transpiration and meteorological factors can improve our knowledge of the mechanisms of vegetation adaptability to a changing environment. However, the controlling factors on the TL remain poorly understood. Therefore, the objective of this study is identifying the temporal dynamics of key controlling factors on the TL, using a typical deciduous broad-leaved tree species(Zenia insigins Chun) of CZ in subtropical humid karst regions. This species is used as an example to explore the characteristics of the TL between SF(sap flow) and hydro-meteorological forcing. Sap flow in these 6 trees was monitored using the thermal dissipation probes(TDP). Results showed that:(1) the peak of diurnal sap flow generally lagged behind PAR but preceded Ta(air temperature), RH(relative humidity) and VPD(vapor pressure deficit), with the mean TL of-67.4 min(PAR), 90.5 min(Ta), 91.6 min(RH) and 92.9 min(VPD), respectively;(2) TL had no significant relationships with the daily mean meteorological factors and soil moisture, but was highly(R^2>0.66) correlated to CRs(changing rates of meteorological factors) in the morning;(3) At seasonal scale, the sap flow rate and TL both were controlled by the seasonality of precipitation and temperature. Overall, the seasonality of the TL was caused by plants' high water loss and strongly active physiological response in hot seasons, leading to close stomata earlier than in cold seasons;(4) The reason why CRs proposed can explain the TL better than mean values of metrological factors is that the CRs considered the distribution and change processes of metrological factors in the daytime. This study may be helpful for understanding the physiological response of vegetation to climatic change, and may be useful for constructing models to simulate transpiration processes more accurately during a day.

Seasonal and reproductive variation in chemical constituents of scent signals in wild giant pandas

Seasonally reproducing animals show many behavioral and physiological changes during the mating period, including increased signaling for intrasexual competition and mate attraction. We collected 102 anogenital gland secretions(AGS) from marking trees in Foping Nature Reserve, and used gas chromatography mass spectrometry to analyze these chemical composition. Of these marks, all but one were from males, confirmed with DNA analysis. We found that several chemical constituents, especially volatile compounds, were present only during the mating season and that the relative abundance of many compounds changed as a function of breeding season, whereas nonvolatile compounds were lower in the mating season. This seasonal variation in chemical composition of AGS most likely plays an important role in governing giant panda reproduction, including mate location, attraction, and male-male competition. The chemical properties of many of these putative chemosignals—such as volatility and longevity—are suggestive of these roles, and undoubtedly contribute to successful reproduction for this species with a characteristically sophisticated chemical communication system. We also found a number of important differences between the chemical constituents of AGS from wild pandas and those found in previous studies with captive pandas, suggesting that inappropriate chemosignal composition may contribute to poor reproductive success in captive breeding programs.

Fingerprinting sediment sources in a typical karst catchment of southwest China

Due to the complex hydrogeological conditions in karst regions,it is difficult to measure sediment source contributions at a catchment scale directly.The objective of this study was to quantify the relative contributions of sediment sources and their temporal variability in a karst catchment in southwest China.Karst depressions can trap eroded sediment similar to a dam or reservoir and,thus,are representative and typical test beds for identifying sediment sources in karst regions.Three sediment cores were taken from a karst depression,58 soil samples from three potential sediment sources were collected,and 18 soil properties were analyzed.The relative contributions of cropland,forestland,and fissure or crack soils were calculated using a multivariate mixing model.The fingerprinting results demonstrated that the cropland was the main sediment source in karst catchment.Specifically,according to the mean sediment contributions of the three deposited sediment cores,the sediment contribution from cropland topsoil was 69.3%,varying from 46.9%to 92.3%,and forestland soil and crack soil accounted for 8.6%and 22.1%of the sediment yield,and varying from 2.8%to 16.5%and 4.8%-36.6%,respectively.This result indicated that great attention should be paid when using only a single core to quantify sediment provenance.Due to the deposited sediment was generally disturbed as cropland in the karst depression,the area that has not been disturbed in recent decades in depression was more appropriate to trace sediment sources in karst catchment.To the best of our knowledge,this study was the first to quantify the contributions of sediment sources in the karst catchment of southwest China.This study provides valuable information and a preliminary reference for applying a composite fingerprinting technique to quantify sediment sources in karst catchments.

Social dominance-related major urinary proteins and the regulatory mechanism in mice

Major urinary proteins(MUPs)have been proven to be non-volatile male pheromones in mice.Here,we aimed to elucidate the relationship between MUPs and dominance hierarchy,and the underlying molecular mechanisms.Dominance–submission relationship was established by chronic dyadic encountering.We found that at the urinary protein level and hepatic mRNA level,the expression of major MUPs,including Mup20,was enhanced in dominant males compared with subordinate males,indicating that MUPs might signal the social status of male mice.Meanwhile,the mRNA level of hepatic corticotropin releasing hormone receptor 2(CRHR2)was higher in subordinate male mice than in dominant male mice.Castration also enhanced the expression of CRHR2,but suppressed that of MUPs.CRHR2 agonist treatment reduced the expression of MUPs in liver.However,male social status failed to exert significant influence on serum testosterone and corticosterone as well as the mRNA expression of their receptors.These findings reveal that some MUPs,especially Mup20,might constitute potential dominance pheromones and could be downregulated by hepatic CRHR2,which is possibly independent of androgen or corticosterone systems.

The miR166 mediated regulatory module controls plant height by regulating gibberellic acid biosynthesis and catabolism in soybean

MicroRNAs(miRNAs)are endogenous small noncoding RNAs that play critical roles in regulating plant growth and development.Here,we used Short Tandem Target Mimic(STTM)technology to generate soybean(Glycine max(L.)Merr.)miRNA knockdown lines and identify miRNAs that regulate plant height,a key agronomic trait that affects yield.STTM166 successfully silenced miR166 in soybean and upregulated the expression of miR166 target genes,such as ATHB14-LIKE.The miR166 knockdown lines(GmSTTM166)displayed a reduced plant height phenotype.Moreover,GmSTTM166 plants contained lower levels of bioactive gibberellic acid(GA3)than wild-type plants,and application of exogenous GA partially rescued the dwarf phenotype of GmSTTM166.Knockdown of miR166 altered the expression of genes involved in GA biosynthesis and catabolism.Further analysis revealed that ATHB14-LIKE directly represses transcription of the GA biosynthesis genes Gm GA1 and Gm GA2,while activating transcription of the GA catabolic gene GIBBERLLIN 2 OXIDASE2(GmGA2ox2).Collectively,these results reveal a pivotal role for miR166 in the genetic control of plant height in soybean,thereby providing invaluable insights for molecular breeding to improve soybean yield.