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101.
Photoperiodic flowering is one of the most important factors affecting regional adaptation and yield in soybean (Glycine max). Plant adaptation to long-day conditions at higher latitudes requires early flowering and a reduction or loss of photoperiod sensitivity; adaptation to short-day conditions at lower latitudes involves delayed flowering, which prolongs vegetative growth for maximum yield potential. Due to the influence of numerous major loci and quantitative trait loci (QTLs), soybean has broad adaptability across latitudes. Forward genetic approaches have uncovered the molecular basis for several of these major maturity genes and QTLs. Moreover, the molecular characterization of orthologs of Arabidopsis thaliana flowering genes has enriched our understanding of the photoperiodic flowering pathway in soybean. Building on early insights into the importance of the photoreceptor phytochrome A, several circadian clock components have been integrated into the genetic network controlling flowering in soybean: E1, a repressor of FLOWERING LOCUS T orthologs, plays a central role in this network. Here, we provide an overview of recent progress in elucidating photoperiodic flowering in soybean, how it contributes to our fundamental understanding of flowering time control, and how this information could be used for molecular design and breeding of high-yielding soybean cultivars. 相似文献
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Chao Tianzhu Lu Liaoxun Zhang Lichen Huang Rong Liu Zhuangzhuang Zhou Binhui Kong Eryan Zhang Zhongjian Lawrence Toby Liang Yinming 《中国科学:生命科学英文版》2021,64(8):1227-1235
Science China Life Sciences - Neutrophils are crucial for immunity and play important roles in inflammatory diseases; however, mouse models selectively deficient in neutrophils are limited, and... 相似文献
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Guangming Li Dejun Kong Yafei Qin Hongda Wang Yonghao Hu Yiming Zhao Jingpeng Hao Hong Qin Dingding Yu Yanglin Zhu Chenglu Sun Hao Wang 《Cytotherapy》2021,23(7):617-626
Background aimsMesenchymal stromal cells and immunosuppressive factor IL-37 can both suppress concanavalin A (Con A)-induced hepatitis in mice. Endometrial regenerative cells (ERCs), novel types of mesenchymal-like stromal cells, possess powerful immunomodulatory effects and are effective in treating various diseases. The aim of this study was to explore the effects of ERCs in suppressing Con A-induced hepatitis and determine whether IL-37 overexpression could enhance the therapeutic effect of ERCs in this process.MethodsERCs were extracted from the menstrual blood of healthy female volunteer donors. The IL-37 gene was transferred into ERCs, and the expression of IL-37 in cells was detected by western blot and enzyme-linked immunosorbent assay. Hepatitis was induced by Con A in C57BL/6 mice that were randomly divided into groups treated with phosphate-buffered saline, ERCs, IL-37 or ERCs transfected with the IL-37 gene (IL-37-ERCs). Cell tracking, liver function, histopathological and immunohistological changes, immune cell proportions and levels of cytokines were measured 24 h after Con A administration.ResultsCompared with ERC or IL-37 treatment, IL-37-ERCs further reduced levels of liver enzymes (alanine aminotransferase and aspartate aminotransferase) and improved histopathological changes in the liver. In addition, IL-37-ERC treatment further reduced the proportions of M1 macrophages and CD4+ T cells and increased the proportion of regulatory T cells. Moreover, IL-37-ERC treatment resulted in lower levels of IL-12 and interferon gamma, and higher level of transforming growth factor beta.ConclusionsThe results of this study suggest that ERCs can effectively alleviate Con A-induced hepatitis. Furthermore, IL-37 overexpression can significantly enhance the therapeutic efficacy of ERCs by augmenting the immunomodulatory and anti-inflammatory properties of ERCs. This study may provide a promising strategy for treatment of T-cell-dependent hepatitis. 相似文献
107.
Zhu Yijing Li Qi Yu Hong Liu Shikai Kong Lingfeng 《Marine biotechnology (New York, N.Y.)》2021,23(5):777-789
Marine Biotechnology - The widely recognized color polymorphisms of molluscan shell have been appreciated for hundreds of years by collectors and scientists, while molecular mechanisms underlying... 相似文献
108.
Animals monitor surrounding dangers independently or cooperatively (synchronized and coordinated vigilance), with independent and synchronized scanning being prevalent. Coordinated vigilance, including unique sentinel behavior, is rare in nature, since it is time‐consuming and limited in terms of benefits. No evidence showed animals adopt alternative vigilance strategies during antipredation scanning yet. Considering the nonindependent nature of both synchronization and coordination, we assessed whether group members could keep alert synchronously or in a coordinated fashion under different circumstance. We studied how human behavior and species‐specific variables impacted individual and collective vigilance of globally threatened black‐necked cranes (Grus nigricollis) and explored behavior‐based wildlife management. We tested both predation risk (number of juveniles in group) and human disturbance (level and distance) effects on individual and collective antipredation vigilance of black‐necked crane families. Adults spent significantly more time (proportion and duration) on scanning than juveniles, and parents with juveniles behaved more vigilant. Both adults and juveniles increased time allocation and duration on vigilance with observer proximity. Deviation between observed and expected collective vigilance varied with disturbance and predation risk from zero, but not significantly so, indicating that an independent vigilance strategy was adopted by black‐necked crane couples. The birds showed synchronized vigilance in low disturbance areas, with fewer juveniles and far from observers; otherwise, they scanned in coordinated fashion. The collective vigilance, from synchronized to coordinated pattern, varied as a function of observer distance that helped us determine a safe distance of 403.75 m for the most vulnerable family groups with two juveniles. We argue that vigilance could constitute a prime indicator in behavior‐based species conservation, and we suggesting a safe distance of at least 400 m should be considered in future tourist management. 相似文献
109.
[目的] 三裂叶豚草是中国重点防控的入侵植物,研究其潜在的适生区分布格局变化对预警防控具有重要意义。[方法] 基于MaxEnt优化模型预测当前及未来(RCP2.6、RCP4.5、RCP8.5)气候情景下三裂叶豚草潜在的地理分布格局。[结果] 当调控倍频(RM)=3.5,FC(特征组合)=LQH(线性、二次型、片段化组合)时为最优模型,MaxEnt模型的预测结果较准确,受试者工作特征曲线下的面积(AUC值)达0.9287;综合8种途径评估出人类活动因子(hfp,贡献率69%)、等温性(bio3,贡献率8.9%)、温度季节变动系数(bio4,贡献率2.9%)、年降水量(bio12,贡献率7.3%)和海拔(ELEV,贡献率3.7%)是制约三裂叶豚草潜在地理分布的主要环境因子;在当前气候情景下,三裂叶豚草的高适生区主要集中在东北平原、江淮地区、京津冀、山东半岛等经济发达地区。[结论] 在未来气候变化情景下,三裂叶豚草在我国的潜在适生区范围总体呈现不同程度的缩减,即丧失率大于增加率;三裂叶豚草将有向南迁移的趋势;最冷月最低温度(bio6)是最不相似变量分析中出现频次最高的因子,表明温度因素对三裂叶豚草潜在地理分布变迁起到重要制约作用。本研究结果可为三裂叶豚草的预防和控制提供理论基础。 相似文献
110.
Jian-Yong Zhang Wei-Ji Wang Jie Kong Qing-Yin Wang 《Russian Journal of Marine Biology》2013,39(2):136-142
Genetic linkage maps of Fenneropenaeus chinensis were constructed using a “double pseudo-testcross” strategy with 200 single nucleotide polymorphisms (SNPs) markers. This study represents the first SNP genetic linkage map for F. chinensis. The parents and F 1 progeny of 100 individuals were used as mapping populations. 21 genetic linkage groups in the male and female maps were identified. The male linkage map was composed of 115 loci and spanned 879.7 cM, with an average intermarker spacing of 9.4 cM, while the female map was composed of 119 loci and spanned 876.2 cM, with an average intermarker spacing of 8.9 cM. The estimated coverage of the linkage maps was 51.94% for the male and 53.77% for the female, based on two estimates of genome length. The integrated map contains 180 markers distributed in 16 linkage groups, and spans 899.3 cM with an average marker interval of 5.2 cM. This SNP genetic map lays the foundation for future shrimp genomics and genetic breeding studies, especially the discovery of gene or regions for economically important traits in Chinese shrimp. 相似文献