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951.
βII spectrin, the most common isoform of non-erythrocyte spectrin, is a cytoskeleton protein present in all nucleated cells. Interestingly, βII spectrin is essential for the development of various organs such as nerve, epithelium, inner ear, liver and heart. The functions of βII spectrin include not only establishing and maintaining the cell structure but also regulating a variety of cellular functions, such as cell apoptosis, cell adhesion, cell spreading and cell cycle regulation. Notably, βII spectrin dysfunction is associated with embryonic lethality and the DNA damage response. More recently, the detection of altered βII spectrin expression in tumors indicated that βII spectrin might be involved in the development and progression of cancer. Its mutations and disorders could result in developmental disabilities and various diseases. The versatile roles of βII spectrin in disease have been examined in an increasing number of studies; nonetheless, the exact mechanisms of βII spectrin are still poorly understood. Thus, we summarize the structural features and biological roles of βII spectrin and discuss its molecular mechanisms and functions in development, homeostasis, regeneration and differentiation. This review highlight the potential effects of βII spectrin dysfunction in cancer and other diseases, outstanding questions for the future investigation of therapeutic targets. The investigation of the regulatory mechanism of βII spectrin signal inactivation and recovery may bring hope for future therapy of related diseases.  相似文献   
952.
Androgen receptor (AR) and its variants play vital roles in development and progression of prostate cancer. To clarify the mechanisms involved in the enhancement of their actions would be crucial for understanding the process in prostate cancer and castration-resistant prostate cancer transformation. Here, we provided the evidence to show that pre-mRNA processing factor 6 (PRPF6) acts as a key regulator for action of both AR full length (AR-FL) and AR variant 7 (AR-V7), thereby participating in the enhancement of AR-FL and AR-V7-induced transactivation in prostate cancer. In addition, PRPF6 is recruited to cis-regulatory elements in AR target genes and associates with JMJD1A to enhance AR-induced transactivation. PRPF6 also promotes expression of AR-FL and AR-V7. Moreover, PRPF6 depletion reduces tumor growth in prostate cancer-derived cell lines and results in significant suppression of xenograft tumors even under castration condition in mouse model. Furthermore, PRPF6 is obviously highly expressed in human prostate cancer samples. Collectively, our results suggest PRPF6 is involved in enhancement of oncogenic AR signaling, which support a previously unknown role of PRPF6 during progression of prostate cancer and castration-resistant prostate cancers.  相似文献   
953.
Yue  Maofeng  Shen  Hao  Ye  Wanhui  Li  Weihua  Chen  Jinfeng 《Biological invasions》2021,23(9):2913-2925

Winter low temperature disturbance in the southern subtropics has important effects on the weed community structure, but the role of uniquely low temperatures in biological invasions is unclear. Here, we examined the competitive effects of an invasive plant, Bidens pilosa L., and its native congener, Bidens biternata (Lour.) Merr. et Sherff, during high and low temperature seasons to determine whether low temperatures promote the competitiveness of B. pilosa in the southern subtropics of China. The growth and physiological responses of the two Bidens species to low (10/5 °C) and optimum (30/25 °C) temperatures were examined to determine how the invasive B. pilosa responds to low temperature stress. Our results showed that the competitive balance index values of B. pilosa in low temperature seasons were significantly higher than those in high temperature seasons, which implied that low temperatures may be more beneficial to the competitiveness of B. pilosa than high temperatures in the southern subtropics. The smaller decline in the relative growth rate and the photosynthetic ability of B. pilosa compared with B. biternata under low temperature stress indicated that the former was less negatively affected by low temperature than the latter. A higher DPPH· (1.1-diphenyl-2-picrylhy-drazyl) scavenging rate and greater heat-stable protein content in B. pilosa under low temperatures might help the invasive plant to maintain more effective physiological functions and thus a higher growth rate. Overall, the uniquely low temperature in the southern subtropics of China is expected to promote the invasiveness of the exotic B. pilosa.

  相似文献   
954.
Infants often experience complementary food-induced diarrhoea (CFID), which occurs when infants switch from breast milk to solid foods. The relative abundances of Prevotella and Rothia were higher in stools of infants with CFID, while the relative abundances of Enterococcus and Escherichia were higher in healthy infants. The abundance of Lactobacillus spp. normally found in breast milk fed to infants with CFID was significantly reduced, and Enterococcus spp. were less abundant when diarrhoea occurred. Furthermore, Lactobacillus and Enterococcus were present as shared bacteria in both mother and infant, and they were considered potential anti-CFID probiotics as their relative abundances in breast milk were negatively correlated to infant CFID. Kyoto encyclopedia of genes and genomes (KEGG) functional analysis showed that the function of amino acid metabolism differed between infants with CFID and healthy infants. Therefore, CFID might be related to the decomposition of proteins in food supplements. The screening revealed seven hydrolytic casein and five hydrolytic casein and rice protein isolates from 320 suspected Lactobacillus and Enterococcus isolates. The animal experiments demonstrated that a mixture of five isolates effectively hydrolysed the casein and rice protein and prevented diarrhoea in young rats. Thus, the occurrence of CFID was found to be closely related to the intestinal and breast milk microbiota, and bacteria that could assist in the digestion of cereal proteins were involved in CFID.  相似文献   
955.
Shan  Mingqiu  Jiang  Yulan  Fu  Yuanyuan  Zhou  Yongyi  Lu  Zhihui  Yu  Sheng  Yan  Hui  Liu  Chanchan  Chen  Peidong  Bao  Beihua  Zhang  Li  Wu  Qinan 《Phytochemistry Reviews》2021,20(5):991-1012
Phytochemistry Reviews - Nepeta tenuifolia (N. tenuifolia) is a common aromatic herb that is widespread in East Asia. The aerial parts and spikes can be used as the traditional phytomedicines for...  相似文献   
956.
Liu  Yue  Sun  Jiandong  Su  Yang  Lin  Jianmin  Lv  Chengyu  Mo  Kaien  Xu  Songhua  Wang  Shie 《Journal of molecular histology》2021,52(5):965-973
Journal of Molecular Histology - Preimplantation embryo development is characterized by drastic nuclear reprogramming and dynamic stage-specific gene expression. Key regulators of this earliest...  相似文献   
957.
林窗环境异质性导致群落物种多样性与系统发育多样性(phylogenetic diversity, PD)存在差异, 研究不同大小的林窗中群落的物种多样性与系统发育多样性有助于揭示林下生物多样性的形成及维持机制。本文以格氏栲(Castanopsis kawakamii)天然林为研究对象, 通过Pearson相关性分析与广义线性模型探讨了林窗内物种多样性与系统发育多样性间的相互关系及其环境影响因素。结果表明: (1)大林窗(面积 > 200 m2)植物种类及多度均高于中林窗(50 m2 ≤ 面积 < 100 m2)、小林窗(30 m2 ≤ 面积 < 50 m2)和非林窗(面积 = 100 m2)。大林窗群落系统发育结构趋于发散, 中、小林窗和非林窗群落系统发育结构受到生境过滤和竞争排斥综合作用。(2)群落系统发育多样性指数与物种丰富度(species richness, SR)、Margalef丰富度指数和Shannon-Wiener指数均呈显著正相关, 这与林窗内稀有种种类组成多于优势种有关。(3)林窗面积对物种多样性存在显著正效应; 土壤全氮含量对系统发育多样性和系统发育结构存在显著正效应。林窗形成提高了格氏栲天然林群落物种多样性和系统发育多样性, 林窗面积与土壤全氮共同驱动了格氏栲天然林林窗物种多样性和系统发育多样性的变化。  相似文献   
958.
本文报道了6个中国被子植物新记录种及1个新记录亚种, 分别是采自西藏的灰滨藜(Atriplex pallida)、类球花藜(Blitum litwinowii)、滨藜状藜(Chenopodium atripliciforme)、土耳其针茅(Stipa turkestanica)、扁果岩蓼(Polygonum cognatum subsp. chitralicum)及新疆的宝格达黄芪(Astragalus baitagensis)和神香草叶千屈菜(Lythrum hyssopifolia), 观察了部分类群的微形态特征并提供了生境或形态图。凭证标本均存放于内蒙古大学植物标本馆(HIMC)。  相似文献   
959.
以中国半翅目等29目昆虫类群(除鞘翅目、双翅目、鳞翅目、膜翅目之外的其他目)为研究对象, 基于2020年度发表的新分类单元与文献资料, 编制了物种名录, 分析了新分类单元的地理分布与模式标本存放情况等。2020年, 中国半翅目等29目昆虫共描述349个新分类单元, 包括新属35个, 新种311个, 新亚种3个; 新种发表的热点地区在我国的西南山地及其邻近地区。模式标本存放单位多达69家, 其中正模标本主要存放在国内保藏机构, 而境外机构保藏的标本较少且以副模标本为主。本年度描述的349个新分类单元由356位作者所贡献, 共发表文献182篇; ZootaxaZooKeys是发表的主要期刊。本次调查为进一步深入研究物种演化的时空格局及生物多样性保护提供了基础数据。同时, 由于人类面临生物多样性急剧下降的威胁, 应加快大数据平台的建设及其多样化信息的挖掘, 支撑生物多样性的研究和保护。  相似文献   
960.
为了及时掌握中国脊椎动物新增物种情况, 本文系统检索和整理了2020年发表的分类学文献, 汇总结果表明: 2020年中国脊椎动物共新增109种, 其中新物种100种, 国家级新记录种9种。包括鱼类新种24种、两栖类新种41种和新记录4种、爬行类新种30种和新记录4种、鸟类新种1种、哺乳类新种4种和新记录1种。上述新增物种中有92种描述报道时应用了分子遗传学证据, 占新增物种数量的84.4%。在新增脊椎动物物种中, 两栖类集中于无尾目、爬行类全部属于有鳞目, 分别有43种和34种, 其累计占比超新增物种总数的70%。在云南、西藏、湖南、贵州、四川等省区发现新物种数量较多, 均有10种及以上, 累计占比超新增物种总数的60%。绝大部分物种为中国学者发表, 绝大多数论文发表于英文期刊。总结数据提示今后需持续加强我国低等脊椎动物多样性的调查研究, 重视运用分子系统学技术进行物种识别。  相似文献   
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