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1.
Zhenzhen Zhang Changjiu He Yu Gao Lu Zhang Yukun Song Tianqi Zhu Kuanfeng Zhu Dongying Lv Jing Wang Xiuzhi Tian Teng Ma Pengyun Ji Wei Cui Guoshi Liu 《Aging cell》2021,20(2)
The fecundity reduction with aging is referred as the reproductive aging which comes earlier than that of chronological aging. Since humans have postponed their childbearing age, to prolong the reproductive age becomes urgent agenda for reproductive biologists. In the current study, we examined the potential associations of α‐ketoglutarate (α‐KG) and reproductive aging in mammals including mice, swine, and humans. There is a clear tendency of reduced α‐KG level with aging in the follicle fluids of human. To explore the mechanisms, mice were selected as the convenient animal model. It is observed that a long term of α‐KG administration preserves the ovarian function, the quality and quantity of oocytes as well as the telomere maintaining system in mice. α‐KG suppresses ATP synthase and alterations of the energy metabolism trigger the nutritional sensors to down‐regulate mTOR pathway. These events not only benefit the general aging process but also maintain ovarian function and delay the reproductive decline. Considering the safety of the α‐KG as a naturally occurring molecule in energy metabolism, its utility in reproduction of large mammals including humans deserves further investigation. 相似文献
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用免疫细胞化学技术观察了单眼剥夺后金黄地鼠视觉中枢GABA神经元分布的变化。结果表明:单眼剥夺后,金黄地鼠视皮层和上丘的GABA阳性神经元暂时性增多,但剥夺后六个月,其数目显著减少。在单眼剥夺前和剥夺后侧膝体中GABA阳性神经元数目没有明显差异。剥夺眼对侧视皮层GABA阳性神经元数比剥夺眼同侧视皮层GABA神经元数目少。单眼剥夺后视觉中枢GABA神经元类型及形态与剥夺前没有差别。晚期单眼剥夺也能引起视觉中枢GABA神经元数量和分布的变化。以上结果表明,单眼剥夺后视觉中枢抑制神经元的结构发生了变化。 相似文献
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Peng Li Liang Xiao Qingzhang Du Mingyang Quan Yuepeng Song Yuling He Weixiong Huang Jianbo Xie Chenfei Lv Dan Wang Jiaxuan Zhou Lianzheng Li Qing Liu Yousry A. El-Kassaby Deqiang Zhang 《Plant biotechnology journal》2023,21(10):2002-2018
Heterozygous alleles are widespread in outcrossing and clonally propagated woody plants. The variation in heterozygosity that underlies population adaptive evolution and phenotypic variation, however, remains largely unknown. Here, we describe a de novo chromosome-level genome assembly of Populus tomentosa, an economic and ecologically important native tree in northern China. By resequencing 302 natural accessions, we determined that the South subpopulation (Pop_S) encompasses the ancestral strains of P. tomentosa, while the Northwest subpopulation (Pop_NW) and Northeast subpopulation (Pop_NE) experienced different selection pressures during population evolution, resulting in significant population differentiation and a decrease in the extent of heterozygosity. Analysis of heterozygous selective sweep regions (HSSR) suggested that selection for lower heterozygosity contributed to the local adaptation of P. tomentosa by dwindling gene expression and genetic load in the Pop_NW and Pop_NE subpopulations. Genome-wide association studies (GWAS) revealed that 88 single nucleotide polymorphisms (SNPs) within 63 genes are associated with nine wood composition traits. Among them, the selection for the homozygous AA allele in PtoARF8 is associated with reductions in cellulose and hemicellulose contents by attenuating PtoARF8 expression, and the increase in lignin content is attributable to the selection for decreases in exon heterozygosity in PtoLOX3 during adaptive evolution of natural populations. This study provides novel insights into allelic variations in heterozygosity associated with adaptive evolution of P. tomentosa in response to the local environment and identifies a series of key genes for wood component traits, thereby facilitating genomic-based breeding of important traits in perennial woody plants. 相似文献
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冬小麦根表面氧化还原活力的研究 总被引:4,自引:1,他引:3
证实了两个不同品种的冬小麦根系表面存在着氧化NADH和还原K3Fe(CN)6的氧化的活力。还原铁氰化物活力在PH5.5到8.5范围内随着PH值升高而增大,温度在15℃到45℃范围内随温度升高还原活力增强,45℃达最高值,55℃时活力急剧下降。 相似文献
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研究了水平沟耕作条件下密度、施肥对谷子产量的影响,寻找最佳施肥和密度以获得最高产量和纯收入,并对株高、叶面积、叶面积系数、蒸腾强度、耗水量等指标作了研究,认为水平沟耕作有良好的经济和生态效益。 相似文献
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Luocheng Lv Zhaofu Liao Jiali Luo Hongyi Chen Hongyan Guo Jifeng Yang Ruijin Huang Qin Pu Hui Zhao Ziqiang Yuan Shanshan Feng Xufeng Qi Dongqing Cai 《Journal of cellular and molecular medicine》2020,24(4):2531-2541
Recent research has revealed that cardiac telocytes (CTs) play an important role in cardiac physiopathology and the regeneration of injured myocardium. Recently, we reported that the adult Xenopus tropicalis heart can regenerate perfectly in a nearly scar‐free manner after injury via apical resection. However, whether telocytes exist in the X tropicalis heart and are affected in the regeneration of injured X tropicalis myocardium is still unknown. The present ultrastructural and immunofluorescent double staining results clearly showed that CTs exist in the X tropicalis myocardium. CTs in the X tropicalis myocardium were mainly twined around the surface of cardiomyocyte trabeculae and linked via nanocontacts between the ends of the telopodes, forming a three‐dimensional network. CTs might play a role in the regeneration of injured myocardium. 相似文献