Glycine metabolomic changes induced by anticancer agents in A549 cells

Amino Acids - Glycine plays a key role in rapidly proliferating cancer cells such as A549 cells. Targeting glycine metabolism is considered as a potential means for cancer treatment. However, the...     

Research progress on gut health of farmers teleost fish: a viewpoint concerning the intestinal mucosal barrier and the impact of its damage

Reviews in Fish Biology and Fisheries - The intestinal mucosal barrier plays a critical role in the maintenance of host health. In farmed teleost fish, the intestinal epithelium is challenged by a...     

Requirements for human embryonic stem cells

‘Requirements for Human Embryonic Stem Cells’ is the first set of guidelines on human embryonic stem cells in China, jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research. This standard specifies the technical requirements, test methods, test regulations, instructions for use, labelling requirements, packaging requirements, storage requirements and transportation requirements for human embryonic stem cells, which is applicable to the quality control for human embryonic stem cells. It was originally released by the China Society for Cell Biology on 26 February 2019 and was further revised on 30 April 2020. We hope that publication of these guidelines will promote institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardization of human embryonic stem cells for applications.     

The mechanism of Single strand binding protein–RecG binding: Implications for SSB interactome function

The Escherichia coli single‐strand DNA binding protein (SSB) is essential to viability where it functions to regulate SSB interactome function. Here it binds to single‐stranded DNA and to target proteins that comprise the interactome. The region of SSB that links these two essential protein functions is the intrinsically disordered linker. Key to linker function is the presence of three, conserved PXXP motifs that mediate binding to oligosaccharide‐oligonucleotide binding folds (OB‐fold) present in SSB and its interactome partners. Not surprisingly, partner OB‐fold deletions eliminate SSB binding. Furthermore, single point mutations in either the PXXP motifs or, in the RecG OB‐fold, obliterate SSB binding. The data also demonstrate that, and in contrast to the view currently held in the field, the C‐terminal acidic tip of SSB is not required for interactome partner binding. Instead, we propose the tip has two roles. First, and consistent with the proposal of Dixon, to regulate the structure of the C‐terminal domain in a biologically active conformation that prevents linkers from binding to SSB OB‐folds until this interaction is required. Second, as a secondary binding domain. Finally, as OB‐folds are present in SSB and many of its partners, we present the SSB interactome as the first family of OB‐fold genome guardians identified in prokaryotes.     

Mapping and characterization of major QTL for spike traits in common wheat

Physiology and Molecular Biology of Plants - The spike traits of wheat can directly affect yield. F2 and F2:3 lines derived from the cross of the multi-spikelet female 10-A and the uni-spikelet...     

极小种群野生植物坡垒的生境特征及其对幼苗多度的影响

极小种群野生植物坡垒(Hopea hainanensis)曾经是热带低地雨林的优势种, 但由于商业采伐和刀耕火种等严重人类干扰及自然更新困难, 致使其种群数量急剧下降到最小可存活的界限, 急需开展种群的拯救恢复工作。而对于坡垒生境适宜性及更新限制的了解, 是进行种群保护及恢复的基础。本文在对野生坡垒种群及其生境因子调查测定的基础上, 分析了生物与非生物生境特征及其对坡垒种群更新幼苗多度的影响。结果表明: 坡垒种群从幼苗至幼树阶段存在着严重的增补限制。坡度小、土壤含水量和有效磷含量高、母株胸径和冠幅较大、伴生种胸高断面积中等的环境是坡垒幼苗较为适宜的生境, 且坡垒幼苗多度与坡度及土壤pH值显著负相关, 与土壤含水量及土壤全磷含量显著正相关。这些研究结果为极小种群野生植物坡垒的就地保护与种群复壮提供了科学依据。     

西双版纳国家级自然保护区蚂蚁-树互作网络空间变异

网络分析(network analysis)可以同时分析群落中的物种多样性和种间关系, 为了解生态群落的稳定性机制提供了新的分析思路和方法。本研究从西双版纳国家级自然保护区的纳板河、勐仑和勐腊(补蚌)三个地点采集了树栖性蚂蚁及树木的种类和数量数据, 对蚂蚁-树组成的二分网络进行了分析, 探讨了3个采样点物种的多样性、网络指标以及群落指标之间的关系。我们采用零模型的方法比较了3个样点的标准化网络参数差异。结果表明: 蚂蚁和树木的物种数以及树的异质性指数(Shannon-Wiener多样性指数、Simpson多样性指数)都呈现出勐仑 > 纳板河 > 补蚌的趋势。树木-蚂蚁的灭绝曲线系数大小关系同样为勐仑 > 纳板河 > 补蚌, 灭绝曲线与树的物种数及异质性指数大小趋势一致, 而与蚂蚁的异质性指数并不吻合。根据Z值的绝对值来看, 网络参数(加权嵌套性、平均连接数、特化水平、模块性、连接度)与群落参数(灭绝曲线系数、生态位重叠)的大小趋势相同, 表现出勐仑 > 纳板河 > 补蚌的趋势。综上所述, 蚂蚁-树互作网络的稳定性(灭绝曲线系数)主要由树的数量和异质性指数决定。网络的加权嵌套性和网络中节点的平均连接数也能促进群落的稳定性。而在一个特化的(数值越大表示专性互作越多)和模块化(具有较多密切互作的节点单元)的网络中, 当低营养级物种灭绝时高营养级物种数量将迅速减少。