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121.
本文报道了河南省新乡地区4-13岁汉族儿童的18项体质指标的测试结果,并计算了8项体质发育指数;分析了本地区儿童生长发育的特点,并与文献资料进行了比较;据有关指数,确定该地区汉族儿童躯干部的体质类型为:长躯干型、窄胸型、窄肩型、窄骨盆型。 相似文献
122.
Down‐regulating Myoferlin inhibits the vasculogenic mimicry of melanoma via decreasing MMP‐2 and inducing mesenchymal‐to‐epithelial transition 下载免费PDF全文
Wenxue Zhang Ai Meng Rongxin Zhang Yan Zhou 《Journal of cellular and molecular medicine》2018,22(3):1743-1754
Vasculogenic mimicry (VM) constitutes a novel approach for tumour blood supply and contributes to tumour metastasis and poor prognosis in patients with melanoma. Myoferlin (MYOF), a type II membrane protein involved in membrane regeneration and repair, is elevated in several malignant tumours, especially in advanced melanomas. This study aims to investigate the role and mechanism of MYOF in the regulation of VM. VM structures were found in 14 of 52 tested melanoma samples, and high MYOF expression correlated with VM structures. According to Kaplan–Meier survival curves, VM channels and elevated MYOF expression both correlated with poor prognosis in melanoma patients. Down‐regulation of MYOF by siRNA severely impaired the capability of A375 cells to form VM structures in vitro. Further studies demonstrated MYOF knockdown inhibited cell migration and invasion, which is required for VM formation, via decreasing MMP‐2 expression as evidenced by Western blotting, RT‐RCP and ELISA results. SB‐3CT, a specific inhibitor of MMP‐2, showed similar inhibiting effects with siMYOF, further supporting that MYOF down‐regulation inhibits MMP‐2 expression to affect VM formation. Moreover, MYOF knockdown suppress VM formation by A375 cells by inducing mesenchymal‐to‐epithelial transition (MET). After down‐regulating MYOF, focal adhesions were enlarged and A375 cells developed into a clear epithelial morphology. Such cells acquired the expression of E‐cadherin at adherens junctions along with a loss of mesenchymal markers, such as Vimentin and Twist1. In conclusion, MYOF plays an important role in VM and knockdown of MYOF suppresses VM formation via decreasing MMP‐2 and inducing MET in A375 melanoma cells. 相似文献
123.
Jiang L Zhang W Xia Z Jiang G Qian Q Li A Cheng Z Zhu L Mao L Zhai W 《Molecular genetics and genomics : MGG》2007,277(3):263-272
Paracentric inversion is known to inhibit genetic recombination between normal and inverted chromosomal segments in heterozygous
arrangements. Insect inversion polymorphisms have been studied to reveal adaptive processes for maintaining genetic variation.
We report the first paracentric inversion in rice (Oryza sativa), which was discovered in our effort to clone the floral organ number gene FON3. Recombination at the FON3 locus on the long arm of chromosome 11 was severely suppressed over a distance of more than 36 cM. An extensive screening
among 8,242 F2 progeny failed to detect any recombinants. Cytological analysis revealed a loop-like structure on pachytene chromosomes,
whereas FISH analysis showed the migration of a BAC clone from a distal location to a position closer to the centromere. Interestingly,
the locations where the genetic recombination suppression began were coincided with the positions of two physical gaps on
the chromosome 11, suggesting a correlation between the physical gaps, the inversion breakpoints. Transposons and retrotransposons,
and tandemly arranged members of gene families were among the sequences immediately flanking the gaps. Taken together, we
propose that the genetic suppression at the FON3 locus was caused by a paracentric inversion. The possible genetic mechanism causing such a spontaneous inversion was proposed. 相似文献
124.
TAC1, a major quantitative trait locus controlling tiller angle in rice 总被引:10,自引:0,他引:10
Yu B Lin Z Li H Li X Li J Wang Y Zhang X Zhu Z Zhai W Wang X Xie D Sun C 《The Plant journal : for cell and molecular biology》2007,52(5):891-898
A critical step during rice (Oryza sativa) cultivation is dense planting: a wider tiller angle will increase leaf shade and decrease photosynthesis efficiency, whereas a narrower tiller angle makes for more efficient plant architecture. The molecular basis of tiller angle remains unknown. This research demonstrates that tiller angle is controlled by a major quantitative trait locus, TAC1 (Tiller Angle Control 1). TAC1 was mapped to a 35-kb region on chromosome 9 using a large F(2) population from crosses between an indica rice, IR24, which displays a relatively spread-out plant architecture, and an introgressed line, IL55, derived from japonica rice Asominori, which displays a compact plant architecture with extremely erect tillers. Genetic complementation further identified the TAC1 gene, which harbors three introns in its coding region and a fourth 1.5-kb intron in the 3'-untranslated region. A mutation in the 3'-splicing site of this 1.5-kb intron from 'AGGA' to 'GGGA' decreases the level of tac1, resulting in a compact plant architecture with a tiller angle close to zero. Further sequence verification of the mutation in the 3'-splicing site of the 1.5-kb intron revealed that the tac1 mutation 'GGGA' was present in 88 compact japonica rice accessions and TAC1 with 'AGGA' was present in 21 wild rice accessions and 43 indica rice accessions, all with the spread-out form, indicating that tac1 had been extensively utilized in densely planted rice grown in high-latitude temperate areas and at high altitudes where japonica rice varieties are widely cultivated. 相似文献
125.
CRISPR‐Cas gene editing holds substantial promise in many biomedical disciplines and basic research. Due to the important functional implications of non‐histone chromosomal protein HMG‐14 (HMGN1) in regulating chromatin structure and tumor immunity, gene knockout of HMGN1 is performed by CRISPR in cancer cells and the following proteomic regulation events are studied. In particular, DIA mass spectrometry (DIA‐MS) is utilized, and more than 6200 proteins (protein‐ FDR 1%) and more than 82 000 peptide precursors are reproducibly measured in the single MS shots of 2 h. HMGN1 protein deletion is confidently verified by DIA‐MS in all of the clone‐ and dish‐ replicates following CRISPR. Statistical analysis reveals 147 proteins change their expressions significantly after HMGN1 knockout. Functional annotation and enrichment analysis indicate the deletion of HMGN1 induces histone inactivation, various stress pathways, remodeling of extracellular proteomes, cell proliferation, as well as immune regulation processes such as complement and coagulation cascade and interferon alpha/ gamma response in cancer cells. These results shed new lights on the cellular functions of HMGN1. It is suggested that DIA‐MS can be reliably used as a rapid, robust, and cost‐effective proteomic‐screening tool to assess the outcome of the CRISPR experiments. 相似文献
126.
细菌在翻译过程中,mRNA受到损伤(如缺失终止密码子)时会使翻译提前终止,导致核糖体熄火,细菌自身会启动核糖体拯救途径。由tmRNA-SmpB介导的反式翻译系统是结核分枝杆菌中的核糖体拯救途径,对结核分枝杆菌的生长繁殖有重大影响。为探究分枝杆菌中反式翻译途径的启动及其功能特点,本研究选取耻垢分枝杆菌为实验菌株,分别以mCherry和egfp作为报告基因,通过在报告基因3′端添加大肠埃希菌终止子序列,构建能在菌体中反映反式翻译表达的报告体系,并初步探究该体系中报告基因的动态表达特点。结果显示,相比正常表达mCherry的对照菌株,实验菌株中表达的错误mCherry蛋白很快被水解,菌体颜色均明显浅于前者,增强绿色荧光蛋白(enhanced green fluorescent protein,EGFP)定量检测数据也显示错误EGFP水平显著低于正常表达的EGFP水平,表明两种反式翻译报告体系均构建成功。报告基因的动态表达数据显示,蛋白出现翻译异常时,耻垢分枝杆菌可在蛋白翻译过程中快速启动反式翻译途径,并于40~45h将不成熟错误蛋白完全水解。本研究构建的反式翻译报告体系可为后续开展分枝杆菌反式翻译途径的功能研究及抗结核药物筛选提供帮助。 相似文献
127.
l‐cysteine desulfhydrase‐related H2S production is involved in OsSE5‐promoted ammonium tolerance in roots of Oryza sativa 下载免费PDF全文
Hongming Guo Heng Zhou Jing Zhang Wenxue Guan Sheng Xu Wenbiao Shen Guohua Xu Yanjie Xie Christine Helen Foyer 《Plant, cell & environment》2017,40(9):1777-1790
Previous studies revealed that rice heme oxygenase PHOTOPERIOD SENSITIVITY 5 (OsSE5) is involved in the regulation of tolerance to excess ammonium by enhancing antioxidant defence. In this study, the relationship between OsSE5 and hydrogen sulfide (H2S), a well‐known signalling molecule, was investigated. Results showed that NH4Cl triggered the induction of l ‐cysteine desulfhydrase (l ‐DES)‐related H2S production in rice seedling roots. A H2S donor not only alleviated the excess ammonium‐triggered inhibition of root growth but also reduced endogenous ammonium, both of which were aggravated by hypotaurine (HT, a H2S scavenger) or dl ‐propargylglycine (PAG, a l ‐DES inhibitor). Nitrogen metabolism‐related enzymes were activated by H2S, thus resulting in the induction of amino acid synthesis and total nitrogen content. Interestingly, the activity of l ‐DES, as well as the enzymes involved in nitrogen metabolism, was significantly increased in the OsSE5‐overexpression line (35S:OsSE5), whereas it impaired in the OsSE5‐knockdown mutant (OsSE5‐RNAi). The application of the HT/PAG or H2S donor could differentially block or rescue NH4Cl‐hyposensitivity or hypersensitivity phenotypes in 35S:OsSE5‐1 or OsSE5‐RNAi‐1 plants, with a concomitant modulation of nitrogen assimilation. Taken together, these results illustrated that H2S function as an indispensable positive regulator participated in OsSE5‐promoted ammonium tolerance, in which nitrogen metabolism was facilitated. 相似文献
128.
成年太行山猕猴(Macaca mulatta tcheliensis)肩关节变量的研究 总被引:6,自引:0,他引:6
本项研究对成年太行山猕猴肩关节变量进行了测量和统计,作了异速生长分析,并对太行山猕猴(M.mulatta tcheliensis)、滇南猕猴(M.mulatta mulatta)、川西猕猴(M.mulatta lasiotis)、湘鄂猕猴(M.mulatta littoralis)肩关节变量进行了比较和聚类分析。与上述3个亚种相比,太行山猕猴较短的肩胛骨、较小的锁肱指数、较大的三角肌止点指数和较小的摆荡指数,表明太行山猕猴肩关节形态结构更适应于地面上的活动,说明其在地面上活动较多,在树上活动较少。 相似文献
129.
Wenxue Zhai Hao Chen Huihuang Yan Changjie Yan Guoliang Wang Lihuang Zhu 《中国科学C辑(英文版)》1999,42(1):68-73
BAC2, a rice BAC clone containing (TTTAGGG)n homologous sequences, was analyzed by Southern hybridization and DNA sequencing of its subclones. It was disclosed that there were many tandem repeated satellite DNA sequences, called TA352, as well as simple tandem repeats consisting of TTTAGGG or its variant within the BAC2 insert. A 0. 8 kb (TTTAGGG)n-containing fragment in BAC2 was mapped in the telomere regions of at least 5 pairs of rice chromosomes by using fluorescencein situ hybridization (FISH). By RFLP analysis of low copy sequences the BAC2 clone was localized in one terminal region of chromosome 6. All the results strongly suggest that the telomeric DNA sequences of rice are TTTAGGG or its variant, and the linked satellite DNA TA352 sequences belong to telomere-associated sequences. 相似文献
130.