作者机构：
[Wu, Hua; Huang, Li; Zhao, Mian; Luo, Zhenhua] Cent China Normal Univ, Sch Life Sci, Int Res Ctr Ecol & Environm, Inst Evolut & Ecol, 152 Luoyulu, Wuhan 430079, Peoples R China.;[Wu, Hua] Cent China Normal Univ, Wuhan 430079, Peoples R China.
通讯机构：
[Wu, Hua] C;Cent China Normal Univ, Wuhan 430079, Peoples R China.
关键词：
MHC class IIB;polymorphism;gene duplication;balancing selection;Rhacophorus omeimontis
摘要：
The worldwide declines in amphibian populations have largely been caused by infectious fungi and bacteria. Given that vertebrate immunity against these extracellular pathogens is primarily functioned by the major histocompatibility complex (MHC) class II molecules, the characterization and the evolution of amphibian MHC class II genes have attracted increasing attention. The polymorphism of MHC class II genes was found to be correlated with susceptibility to fungal pathogens in many amphibian species, suggesting the importance of studies on MHC class II genes for amphibians. However, such studies on MHC class II gene evolution have rarely been conducted on amphibians in China. In this study, we chose Omei treefrog (Rhacophorus omeimontis), which lived moist environments easy for breeding bacteria, to study the polymorphism of its MHC class II genes and the underlying evolutionary mechanisms. We amplified the entire MHC class IIB exon 2 sequence in the R. omeimontis using newly designed primers. We detected 102 putative alleles in 146 individuals. The number of alleles per individual ranged from one to seven, indicating that there are at least four loci containing MHC class IIB genes in R. omeimontis. The allelic polymorphism estimated from the 102 alleles in R. omeimontis was not high compared to that estimated in other anuran species. No significant gene recombination was detected in the 102 MHC class IIB exon 2 sequences. In contrast, both gene duplication and balancing selection greatly contributed to the variability in MHC class IIB exon 2 sequences of R. omeimontis. This study lays the groundwork for the future researches to comprehensively analyze the evolution of amphibian MHC genes and to assess the role of MHC gene polymorphisms in resistance against extracellular pathogens for amphibians in China.
作者机构：
[Huang, Shuang-Quan; Sun, Shi-Guo] Cent China Normal Univ, Sch Life Sci, Wuhan 430079, Peoples R China.;[Wang, Xiang-Ping] Wuhan Univ, Coll Life Sci, Wuhan 430072, Peoples R China.
通讯机构：
[Huang, Shuang-Quan] C;Cent China Normal Univ, Sch Life Sci, Wuhan 430079, Peoples R China.
摘要：
Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a positive relationship between pollen size and style length. Five floral traits were observed to be correlated among 42 bumblebee-pollinated Pedicularis species (Orobanchaceae) in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin's functional hypothesis between pollen size and stigma depth.
作者机构：
[Yang X.; Du J.; Zhu Y.; Zou J.; Yu J.; Zhu J.] School of Life Sciences, Central China Normal University, Wuhan, 430079, China
通讯机构：
[Xu Yang] S;School of Life Sciences, Central China Normal University, Wuhan, China
关键词：
H_2O_2;glutathione;oxidative stress;TSLP
摘要：
With increasing industrialization, numerous air pollutants are generated. This research aimed to investigate the effects of inhalation of oxidative pollutants. H_2O_2 was used to simulate oxidative air pollutants, and glutathione, a reducing agent that is widely distributed in organisms, was used as an antagonist, to protect cells from oxidative stress. H_2O_2 was diluted using two gradients (0.05 mM, 0.20 mM, 0.80 mM, 3.20 mM and 0.05 mM, 0.10 mM, 0.15 mM, 0.20 mM) and GSH was dissolved at 20 μM. MTT, MDA, ROS, GSH, and TSLP were used as biomarkers to evaluate oxidative stress and possible resulting molecular events. A dose-response relationship was observed between H_2O_2 concentrations and the above-mentioned biomarkers. Glutathione significantly reduced levels of oxidative stress.
摘要：
The secondary cell wall in mature cotton fibers contains over 90% cellulose with low quantities of xylan and lignin. However, little is known regarding the regulation of secondary cell wall biosynthesis in cotton fibers. In this study, we characterized an R2R3-MYB transcription factor, GhMYB7, in cotton. GhMYB7 is expressed at a high level in developing fibers and encodes a MYB protein that is targeted to the cell nucleus and has transcriptional activation activity. Ectopic expression of GhMYB7 in Arabidopsis resulted in small, curled, dark green leaves and also led to shorter inflorescence stems. A cross-sectional assay of basal stems revealed that cell wall thickness of vessels and interfascicular fibers was higher in transgenic lines overexpressing GhMYB7 than in the wild type. Constitutive expression of GhMYB7 in Arabidopsis activated the expression of a suite of secondary cell wall biosynthesis-related genes (including some secondary cell wall-associated transcription factors), leading to the ectopic deposition of cellulose and lignin. The ectopic deposition of secondary cell walls may have been initiated before the cessation of cell expansion. Moreover, GhMYB7 was capable of binding to the promoter regions of AtSND1 and AtCesA4, suggesting that GhMYB7 may function upstream of NAC transcription factors. Collectively, these findings suggest that GhMYB7 is a potential transcriptional activator, which may participate in regulating secondary cell wall biosynthesis of cotton fibers.
作者：
Zhang, Zhongchun;Xie, Qingqing;Jobe, Timothy O.;Kau, Andrew R.;Wang, Cun;...
期刊：
分子植物,2016年9(3):481-484 ISSN：1674-2052
通讯作者：
Julian I. Schroeder
作者机构：
[Jobe, Timothy O.; Kau, Andrew R.; Wang, Cun; Schroeder, Julian I.] Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA 92093-0116, USA;School of Life Sciences, Central China Normal University, Wuhan 430079, Hubei, P.R. China;Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, Hubei, P.R. China;[Wang, Qiuquan] Department of Chemistry & the MOE Key Lab of Spectrochemical Analysis and Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005, China;[DavidG. Mendoza-Cózatl] Division of Plant Sciences, C.S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
通讯机构：
[JulianI. Schroeder] D;Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA 92093-0116, USA
关键词：
detoxification;Cadmium;phytochelatins
摘要：
Glutathione (GSH) is an essential tri-peptide important for several plant processes, including the control of cellular redox status, detoxification of xenobiotics, root development, heavy metal transport and resistance, and long-distance transport of organic sulfur.Cadmium and arsenic are detoxified by small GSH-derived peptides, called phytochelatins (PCs). Phytochelatins are rapidly synthesized in response to toxic metal exposure and have long been known to play an integral role in metal(loid) detoxification in plants. However, while phytochelatins are largely synthesized in roots, GSH is mainly synthesized in chloroplasts and transported in the phloem (Wachter et al., 2005; Mendoza-Cozatl et al., 2008). Thus, GSH transport from shoots to roots is critical for phytochelatin synthesis in plants. However, genes encoding plasma membrane GSH-specific transporters remain largely unknown (Zechmann, 2014; Pike et al., 2009; Cagnac et al., 2004).
摘要：
中国哺乳动物区系有鲜明的特色:有青藏高原分布的特有种属,有第三纪孑遗动物——大熊猫科和白鱀豚科,世界一半以上的鼠兔科动物为中国特有种,中国还是世界有蹄类最丰富的国家。新世纪以来,世界哺乳动物分类体系发生了变化,中国也发现一批哺乳动物新种和新记录种。因此,有必要对中国哺乳动物多样性名录进行及时更新和完善。我们在《中国生物多样性红色名录·哺乳动物卷》的编研中,对中国哺乳动物的目级阶元采用在系统发育基因组学已经取得一致意见的方案;在科及以下阶元以《中国哺乳动物种与亚种分类名录与分布大全》和Mammal Species of the World:A Taxonomic and Geographic Reference（第3版）的分类系统为基础,有蹄类的分类采用Ungulate Taxonomy分类系统;收集整理了中国（包括台湾地区）所有哺乳动物资料,增加了截至2015年3月31日学术期刊发表的中国哺乳动物新种和新记录种,通过会议评审和通讯评审,调整了一些物种的名称和分类地位,确定了《中国哺乳动物名录（2015）》。该名录收录了中国现有哺乳动物12目55科245属673种,其中,新种18种（包括11种最近发现的或利用分子生物学方法确定的、尚有争议的新种）、新记录种18种、60个亚种提升为种。根据研究结果和专家意见,剔除了52种哺乳动物。此外,中国分类学家对新版名录中的20种啮类（Glires）的分类地位持不同意见,这些种类需要进一步研究。以《中国哺乳动物名录（2015）》收录的中国哺乳动物种数与其他国家比较,中国哺乳动物种数超过IUCN（2014）报道的世界哺乳动物排序第一的印度尼西亚（670种）。中国有150种特有哺乳动物,特有种比例为22.3%。兔形目特有种比例达43%,鼠兔科特有种比例更高达52%。劳亚食虫目的特有种比例为35%。中国灵长目、啮齿目和翼手目特有种比例约占各目总种数的1/5,翼手目特有种包括近十年发表、模式产地为中国的12个蝙蝠新种。《中国哺乳动物名录（2015）》为生物多样性研究与保护提供了最新的本底资料。
