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941.
942.
Chiyu Li Jia Chen Xiaoyan Li Xin Zhang Ying Liu Sirui Zhu Long Wang Heping Zheng Sheng Luan Jiada Li Feng Yu 《植物学报(英文版)》2022,64(10):1901-1915
Plant shoot phototropism is triggered by the formation of a light-driven auxin gradient leading to bending growth. The blue light receptor phototropin 1(phot1) senses light direction, but how this leads to auxin gradient formation and growth regulation remains poorly understood. Previous studies have suggested phot1’s role for regulated apoplastic acidification, but its relation to phototropin and hypocotyl phototropism is unclear. Herein, we show that blue light can cause phot1 to interact with... 相似文献
943.
Wenqiao He Yuhan Gao Yuqi Wen Xuemei Ke Zejin Ou Jiaqi Fu Mingji Cheng Yun Mo Qing Chen 《中国病毒学》2022,37(2):215-222
Bocaviruses are associated with many human infectious diseases, such as respiratory tract infections, gastroenteritis, and hepatitis. Rats are known to be reservoirs of bocaviruses, including rodent bocavirus and rat bocavirus. Recently, ungulate bocaparvovirus 4, a known porcine bocavirus, has also been found in rats. Thus, investigating bocaviruses in rats is important for determining the origin of the viruses and preventing and controlling their transmission. To the best of our knowledge, no study to date has investigated bocaviruses in the livers of rats. In this report, a total of 624 rats were trapped in southern China between 2014 and 2017. Liver and serum samples from rats were tested for the prevalence of bocaviruses using PCR. Sequences related to ungulate bocaparvovirus 4 and rodent bocavirus were detected in both liver and serum samples. Interestingly, the prevalence of ungulate bocaparvovirus 4 (reference strain:KJ622366.1) was higher than that of rodent bocavirus (reference strain:KY927868.1) in both liver (2.24% and 0.64%, respectively) and serum samples (2.19% and 0.44%, respectively). The NS1 regions of ungulate bocaparvovirus 4 and rodent bocavirus related sequences displayed over 84% and 88% identity at the nucleic acid and amino acid levels, respectively. Furthermore, these sequences had similar genomic structure, genomic features, and codon usage bias, and shared a common ancestor. These viruses also displayed greater adaptability to rats than pigs. Our results suggested that ungulate bocaparvovirus 4 and rodent bocavirus may originate from rats and may be different genotypes of the same bocavirus species. 相似文献
944.
Chromatin modifications have been comprehensively illustrated to play important roles in gene regulation and cell diversity in recent years. Given the rapid accumulation of genome-wide chromatin modification maps across multiple cell types, there is an urgent need for computational methods to analyze multiple maps to reveal combinatorial modification patterns and define functional DNA elements, especially those are specific to cell types or tissues. In this current study, we developed a computational method using differential chromatin modification analysis (dCMA) to identify cell-type-specific genomic regions with distinctive chromatin modifications. We then apply this method to a public data set with modification profiles of nine marks for nine cell types to evaluate its effectiveness. We found cell-type-specific elements unique to each cell type investigated. These unique features show significant cell-type-specific biological relevance and tend to be located within functional regulatory elements. These results demonstrate the power of a differential comparative epigenomic strategy in deciphering the human genome and characterizing cell specificity. 相似文献
945.
946.
A possible strategy against head and neck cancer: in silico investigation of three-in-one inhibitors
Yung-An Tsou Kuan-Chung Chen Su-Sen Chang Yeong-Ray Wen 《Journal of biomolecular structure & dynamics》2013,31(12):1358-1369
Overexpression of epidermal growth factor receptor (EGFR), Her2, and uroporphyrinogen decarboxylase (UROD) occurs in a variety of malignant tumor tissues. UROD has potential to modulate tumor response of radiotherapy for head and neck cancer, and EGFR and Her2 are common drug targets for the treatment of head and neck cancer. This study attempts to find a possible lead compound backbone from TCM Database@Taiwan (http://tcm.cmu.edu.tw/) for EGFR, Her2, and UROD proteins against head and neck cancer using computational techniques. Possible traditional Chinese medicine (TCM) lead compounds had potential binding affinities with EGFR, Her2, and UROD proteins. The candidates formed stable interactions with residues Arg803, Thr854 in EGFR, residues Thr862, Asp863 in Her2 protein, and residues Arg37, Arg41 in UROD protein, which are key residues in the binding or catalytic domain of EGFR, Her2, and UROD proteins. Thus, the TCM candidates indicated a possible molecule backbone for evolving potential inhibitors for three drug target proteins against head and neck cancer.An animated interactive 3D complement (I3DC) is available in Proteopedia at http://proteopedia.org/w/Journal:JBSD:35 相似文献
947.
948.
Amanda P. Waller Michael George Anuradha Kalyanasundaram Chen Kang Muthu Periasamy Keli Hu Véronique A. Lacombe 《生物化学与生物物理学报:疾病的分子基础》2013,1832(1):121-127
Glucose uptake from the bloodstream is the rate-limiting step in whole body glucose utilization, and is regulated by a family of membrane proteins called glucose transporters (GLUTs). Although GLUT4 is the predominant isoform in insulin-sensitive tissues, there is recent evidence that GLUT12 could be a novel second insulin-sensitive GLUT. However, its physiological role in the heart is not elucidated and the regulation of insulin-stimulated myocardial GLUT12 translocation is unknown. In addition, the role of GLUT12 has not been investigated in the diabetic myocardium. Thus, we hypothesized that, as for GLUT4, insulin regulates GLUT12 translocation to the myocardial cell surface, which is impaired during diabetes. Active cell surface GLUT (-4 and -12) content was quantified (before and after insulin stimulation) by a biotinylated photolabeled assay in both intact perfused myocardium and isolated cardiac myocytes of healthy and type 1 diabetic rodents. GLUT localization was confirmed by immunofluorescent confocal microscopy, and total GLUT protein expression was measured by Western blotting. Insulin stimulation increased translocation of GLUT-4, but not -12, in the healthy myocardium. Total GLUT4 content of the heart was decreased during diabetes, while there was no difference in total GLUT12. Active cell surface GLUT12 content was increased in the diabetic myocardium, potentially as a compensatory mechanism for the observed downregulation of GLUT4. Collectively, our data suggest that, in contrast to GLUT4, insulin does not mediate GLUT12 translocation, which may function as a basal GLUT located primarily at the cell surface in the myocardium. 相似文献
949.
Xiaolu Qu Hua Zhang Yurong Xie Juan Wang Naizhi Chen Shanjin Huang 《The Plant cell》2013,25(5):1803-1817
Apical actin filaments are crucial for pollen tube tip growth. However, the specific dynamic changes and regulatory mechanisms associated with actin filaments in the apical region remain largely unknown. Here, we have investigated the quantitative dynamic parameters that underlie actin filament growth and disappearance in the apical regions of pollen tubes and identified villin as the major player that drives rapid turnover of actin filaments in this region. Downregulation of Arabidopsis thaliana VILLIN2 (VLN2) and VLN5 led to accumulation of actin filaments at the pollen tube apex. Careful analysis of single filament dynamics showed that the severing frequency significantly decreased, and the lifetime significantly increased in vln2 vln5 pollen tubes. These results indicate that villin-mediated severing is critical for turnover and departure of actin filaments originating in the apical region. Consequently, the construction of actin collars was affected in vln2 vln5 pollen tubes. In addition to the decrease in severing frequency, actin filaments also became wavy and buckled in the apical cytoplasm of vln2 vln5 pollen tubes. These results suggest that villin confers rigidity upon actin filaments. Furthermore, an observed decrease in skewness of actin filaments in the subapical region of vln2 vln5 pollen tubes suggests that villin-mediated bundling activity may also play a role in the construction of actin collars. Thus, our data suggest that villins promote actin turnover at pollen tube tips and facilitate the construction of actin collars. 相似文献
950.
陈斌 《Entomologia Sinica》1997,(4)
伪叶甲科Lagriidae是鞘翅目的一个小科,全世界已知约2450种。过去有17位外国学者零星地记述了我国该科昆虫22属和124种6变种。1991年以来作者系统地研究了该科的分类、雄性外生殖器形态结构、系统发育和地理分布。本文报道莫伪叶甲属Merklia力和粗伪叶甲属Pachystira二个新属,及两斑莫伪叶甲Merkliabimaculata和凹翅粗伪叶甲Pachystiraimpressipennis二个新种。 相似文献