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71.
Comparative analysis of the pig BAC sequence involved in the regulation of myostatin gene 总被引:2,自引:2,他引:0
YU Zhengquan LI Yan MENG Qingyong YUAN Jing ZHAO Zhihui LI Wei HU Xiaoxiang YAN Bingxue FAN Baoliang YU Shuyang & LI Ning .State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China .Beijing Genomics Institute / Genomics Bioinformatics Center Institute of Genetics Development Biology Chinese Academy of Sciences Beijing China 《中国科学:生命科学英文版》2005,48(2):168-180
Myostatin (GDF-8, MSTN) is a member of trans- forming growth factors (TGF-β) superfamily, which was first described by McPherron et al. in 1997[1]. Myostatin appears to act as a negative regulator of muscle development and controls not only fibre size but also fibre number[2,3]. Mutations in the third exon of the myostatin gene have been shown to cause dou- ble muscling in cattle[4]. By knocking out the gene of myostatin in mice, they were able to show that the transgenic mice developed … 相似文献
72.
Kinetochores are large protein complexes that bind to centromeres. By interacting with microtubules and their associated motor proteins, kinetochores both generate and regulate chromosome movement. Kinetochores also function in the spindle checkpoint; a surveillance mechanism that ensures that metaphase is complete before anaphase begins. Although the ultrastructure of plant kinetochores has been known for many years, only recently have specific kinetochore proteins been identified. The recent data indicate that plant kinetochores contain homologs of many of the proteins implicated in animal and fungal kinetochore function, and that the plant kinetochore is a redundant structure with distinct biochemical subdomains. 相似文献
73.
74.
原位PCR和原位杂交检测蛋鸡J亚群禽白血病病毒 总被引:4,自引:0,他引:4
根据ALV_J原型株HPRS10 3株gp85基因的内部序列 ,和pol基因的 3′端设计一对引物H5 H7。从发生ML病死蛋用型鸡的肿瘤、骨髓、肝脏、脾脏和输卵管组织中提取总RNA ,反转录为cDNA ,经PCR扩增得到长度为 5 4 5bp的ALV_JcDNA特异性探针。探针定位于 5 2 5 8~ 5 80 2bp。将病鸡的组织石蜡切片置HybaidExpress原位PCR仪平台上 ,以H5 H7为引物进行原位PCR扩增。应用地高辛标记的cDNA探针对原位PCR扩增后切片进行了原位杂交检测。结果在待检组织肿瘤组织、十二指肠、骨髓中出现明显的阳性信号。睾丸、肺、胰腺、大脑、输卵管、肾脏均检出散在的阳性信号。这是国内外首次从分子水平证明蛋鸡J亚群禽白血病。 相似文献
75.
徐建龙 王俊敏 骆荣挺 张铭铣 蒋兴村 李金国XU Jian-long WANG Jun-min LUO Rong-ting ZHANG Ming-xian JIANG Xing-cun LI Jin-guo 《遗传》2002,24(4):431-123
对粳稻农垦58经空间诱变产生的大粒型突变体进行大粒型性状的遗传分析和育种应用研究。结果表明,大粒型突变体的籽粒大小(以籽粒体积表示)表现为受多基因控制的数量性状。大粒型突变体谷粒细长,具馨香味,外观品质优,对粳稻的亲和性好,是一个罕见的优质米资源。以大粒型突变体为供体,高产、外观米质差的晚粳推广品种为受体,采用不饱和回交结合分离世代糙米外观品质鉴定的方法,将大粒型突变体的优质性状导入晚粳背景,选育出外观米质优的晚粳新品系。对采用不饱和回交方法改良数量性状进行了讨论。
Abstract:The inheritance and utilization of a stable large-grain mutant,selected from the induced generation derived from japonica Nongkeng 58 after space treatment carried by recoverable satellite,were analyzed.The results indicated that the grain volume of the large-grain mutant was quantitative trait controlled by multiple genes.The large-grain mutant had characteristics of slender grain,favorable scent,high apparent grain quality and good compatibility with japonica,and can be used as a valuable resource for improving grain quality.When high yield japonica variety with bad looking quality was used as a recurrent parent to cross with the mutant and a procedure of a limited backcross combined with identification of brown rice quality in segregation generations was applied,some japonica lines with good looking quality were developed.The utility of the limited backcross method for improvement of quantitative traits was discussed. 相似文献
76.
RAB5A基因表达改变对人肺腺癌细胞系GLC-82和SPC-a1的分化和侵袭特性影响 总被引:8,自引:0,他引:8
为探讨RAB5A基因对两种人肺腺癌细胞系GLC-82和SPC-al分化及侵袭特性的影响。利用细胞转染技术将构建的RAB5A反义RNA重组质粒(pcDNA3-AntiRAB5A)和RAB5A正义真核表达载体分别转染入低分化人肺腺癌细胞系GLC-82和低转移人肺腺癌细胞系SPC-al中,在稳定筛选后,通过裸鼠体内实验和体外人工基底膜侵袭和细胞趋化运动实验,观察观察转染后细胞分化和转移特性的改变,观察转染前后细胞,发现转染后GLC-82细胞体外侵袭重组基底膜能力及趋化运动能力降低(t检验P<0.02);裸鼠体内成瘤实验,瘤块切片病理观察转染后GLC-82细胞出现腺腔样及基底模样结构,分化程度增高,转染后SPC-al细胞体外趋化运动能力,侵袭重组基底膜能力均增强(t检验P<0.02)。RAB5A基因通过影响细胞的体外趋化运动能力,侵袭重组基底膜能力等对GLC-82和SPC-al细胞的侵袭表型形成及GLC-82细胞的分性发挥重要作用。 相似文献
77.
Han we i Jiang Liu Wang Yingxia Cui Znipeng Xu Ionghang Guo Dongkai Cheng Peng Xu Wen Yu Qinfihua Shi 《遗传学报》2014,41(3):177-185
Reciprocal translocation is one of the most common structural chromosomal rearrangements in human beings; it is widely recognized to be associated with male infertility. This association is mainly based on the abnormal chromosome behavior of the translocated chromosomes and sex chromosomes during meiosis prophase I in reciprocal translocation carriers. However, the underlying mechanisms are not completely known. Here we report a reciprocal translocation carrier of t(8;15), who is oligozoospermic due to apoptosis of primary spermatocytes and to premature germ cell desquamation from seminiferous tubules. Further analysis showed abnormal synapsis and recombination frequency in this patient, indicating a connection between chromosome behavior and apoptosis of primary spermatocytes. We also compared these observations with recently reported findings on spermatogenesis defects in reciprocal translocation carriers, and discuss the possible mechanisms underlying both common and unique phenotypes of reciprocal translocations involving different chromosomes with the aim of further understanding the regulation of human spermatogenesis. 相似文献
78.
XIA HaiYong ZHAO JianHua SUN JianHao XUE YanFang EAGLING Tristan BAO XingGuo ZHANG FuSuo LI Long 《中国科学:生命科学英文版》2014,57(3):362-362
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79.
80.
By nature,biomarker is the measurable change associated with a physiological or pathophysiological process.Unlike blood which has mechanisms to minimize changes and to keep the internal environment homeostatic,urine is more likely to reflect changes of the body and is a better biomarker source.Because of its potential in biomarker discovery,urinary proteins should be preserved comprehensively as the duration of the patients’corresponding medical records.Here,we propose a method to adsorb urinary proteins onto a membrane we named Urimem.This simple and inexpensive method requires minimal sample handling,uses no organic solvents,and is environmentally friendly.Urine samples were filtered through the membrane,and urinary proteins were adsorbed onto the membrane.The proteins on the membrane were dried and stored in a vacuum bag,which keeps the protein pattern faithfully preserved.The membrane may even permit storage at room temperature for weeks.Using this simple and inexpensive method,it is possible to begin preserving urine samples from all consenting people.Thus,medical research especially biomarker research can be conducted more economically.Even more objective large-scale prospective studies will be possible.This method has the potential to change the landscape of medical research and medical practice. 相似文献