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151.
Professor Wen-Tsai Wang (王文采, June 5, 1926–November 16, 2022) was an academician of the Chinese Academy of Sciences (CAS) and a legendary plant taxonomist at the Institute of Botany of CAS (Fig.1). Herein, we organize a virtual special issue in Journal of Systematics and Evolution (JSE) to celebrate the legacy and life of Professor Wang, who was a leading plant taxonomist in China and made important contributions toward advancing the understanding of the flora of China, the biogeography of eastern Asia, and biodiversity research in the vast Hengduan Mountains. He served as the Editor-in-Chief of Acta Phytotaxonomica Sinica (now JSE) for 6 years from 1982 to 1988, and trained several generations of plant taxonomists in China (Li,2001). 相似文献
152.
Teng Man Zhu Zhi-Jian Yao Yongxiu Nair Venugopal Zhang Gai-Ping Luo Jun 《中国科学:生命科学英文版》2023,66(2):251-268
Science China Life Sciences - Over the past two decades, numerous non-coding RNAs (ncRNAs) have been identified in different biological systems including virology, especially in large DNA viruses... 相似文献
153.
Cryptobia salmositica (pathogenic and vaccine strains), Cryptobia bullocki (pathogenic), and Cryptobia catostomi (nonpathogenic) have similar oxygen consumption rates (0.17 +/- 0.01 nm O2/10(6) parasites). Incubation with sodium azide (5 microliters of a 1-M solution to 1 ml of parasite suspension, i.e., a 5-mM final concentration) reduced the oxygen consumption by approximately 4.5-fold. Motility of the parasites was also greatly reduced in sodium azide. The oxygen consumption and motility of the parasites returned to preazide treatment levels when the azide was removed even after 24 hr of incubation in sodium azide. The activities of hexokinase, pyruvate kinase, and cytochrome C oxidase were not detected in the 3 species of Cryptobia. 相似文献
154.
Trypanosoma catostomi was found in 36.2% of 558 white suckers (Catostomus commersoni) from Ontario, Canada. The abundance of Actinobdella inequiannulata was 35% (68 leeches/197 suckers examined for leeches). The susceptibility of 3 species of leeches (Hemiclepsis marginata, Desserobdella phalera, and A. inequiannulata) and 7 species of fishes (C. commersoni, Amia calva, Anguilla rostrata, Ictalurus nebulosus, Oncorhynchus mykiss, Perca flavescens, and Esox lucius) to infection with T. catostomi was examined. Metatrypanosomes were found in the crop and proboscis sheath of 13 of 21 A. inequiannulata and in the crop of 10 of 12 H. marginata and 1 of 21 D. phalera. Only flagellates from A. inequiannulata were infective to C. commersoni. Cultured T. catostomi infected C. commersoni and A. calva but not any other fish species. Laboratory-reared C. commersoni were more susceptible than wild-caught specimens. Cultured Trypanosoma phaleri did not infect its natural host, A. calva. Host specificity should be established experimentally before a specific diagnosis is made. Cultures may be useful in simulating factors that affect development in the vector. 相似文献
155.
Shu-Mei Jiang Long Zhang Jun Hu Rui Shi Guang-He Zhou Yu-Hong Chen Wei-Bo Yin Richard R-C Wang Zan-Min Hu 《Génome》2004,47(6):1114-1121
The alien addition line TAI-27 contains a pair of chromosomes of Thinopyrum intermedium that carry resistance against barley yellow dwarf virus (BYDV). A subtractive library was constructed using the leaves of TAI-27, which were infected by Schizaphis graminum carrying the GAV strain of BYDV, and the control at the three-leaf stage. Nine differentially expressed genes were identified from 100 randomly picked clones and sequenced. Two of the nine clones were highly homologous with known genes. Of the remaining seven cDNA clones, five clones matched with known expressed sequence tag (EST) sequences from wheat and (or) barley whereas the other two clones were unknown. Five of the nine differentially expressed sequences (WTJ9, WTJ11, WTJ15, WTJ19, and WTJ32) were highly homologous (identities >94%) with ESTs from wheat or barley challenged with pathogens. These five sequences and another one (WTJ18) were also highly homologous (identities >86%) with abiotic stress induced ESTs in wheat or barley. Reverse Northern hybridization showed that seven of the nine differentially expressed cDNA sequences hybridized with cDNA of T. intermedium infected by BYDV. Three of these also hybridized with cDNA of line 3B-2 (a parent of TAI-27) infected by BYDV. The alien chromosome in TAI-27 was microdissected. The second round linker adaptor mediated PCR products of the alien chromosomal DNA were labeled with digoxygenin and used as the probe to hybridize with the nine differentially expressed genes. The analysis showed that seven differentially expressed genes were homologous with the alien chromosome of TAI-27. These seven differentially expressed sequences could be used as ESTs of the alien chromosome of TAI-27. This research laid the foundation for screening and cloning of new specific functional genes conferring resistance to BYDV and probably other pathogens. 相似文献
156.
Construction and characterization of two rice bacterial artificial chromosome libraries from the parents of a permanent recombinant inbred mapping population 总被引:13,自引:0,他引:13
Hong-Bin Zhang Sangdun Choi Sung-Sick Woo Zhikang Li Rod A. Wing 《Molecular breeding : new strategies in plant improvement》1996,2(1):11-24
Rice is a leading grain crop and the staple food for over half of the world population. Rice is also an ideal species for genetic and biological studies of cereal crops and other monocotyledonous plants because of its small genome and well developed genetic system. To facilitate rice genome analysis leading to physical mapping, the identification of molecular markers closely linked to economic traits, and map-based cloning, we have constructed two rice bacterial artificial chromosome (BAC) libraries from the parents of a permanent mapping population (Lemont and Teqing) consisting of 400 F9 recombinant inbred lines (RILs). Lemont (japonica) and Teqing (indica) represent the two major genomes of cultivated rice, both are leading commercial varieties and widely used germplasm in rice breeding programs. The Lemont library contains 7296 clones with an average insert size of 150 kb, which represents 2.6 rice haploid genome equivalents. The Teqing library contains 14208 clones with an average insert size of 130 kb, which represents 4.4. rice haploid genome equivalents. Three single-copy DNA probes were used to screen the libraries and at least two overlapping BAC clones were isolated with each probe from each library, ranging from 45 to 260 kb in insert size. Hybridization of BAC clones with chloroplast DNA probes and fluorescent in situ hybridization using BAC DNA as probes demonstrated that both libraries contain very few clones of chloroplast DNA origin and are likely free of chimeric clones. These data indicate that both BAC libraries should be suitable for map-based cloning of rice genes and physical mapping of the rice genome. 相似文献
157.
158.
ZHANG Junwu QIAO Jun SONG Wenfeng QIU Zhiming 《中国科学:生命科学英文版》1996,39(3):329-336
A permanent lymphocyte cell line of a heterozygote with Yunnanese (Aγδβ)0-thalassemia deletion, associated with an increased production of Cry globin in adult, was founded using Epstein-Barr virus transformation. The hybrids of the lymphocyte cell and mouse erythroleukemia cell (MEL) were achieved and the hybrids containing human chromosome 11 were selected with the monoclonal antibody 53/6. The subclones containing only either the normal or the abnormal human chromosome 11 were separated and the expression of the human globin genes was studied. Expression of the β-globin gene, but not the Cγ and Aγ, was observed in the hybrids containing only the normal human chromosome 11, while active expression of the Cγ globin gene was observed in the hybrids containing only the abnormal human chromosome 11. These results have confirmed that the DNA deletion in the β-globin gene cluster is the cause of persistent active expression of the Cγ globin gene in the Yunnanese mutant. 相似文献
159.
野生猕猴声行为的研究 总被引:4,自引:2,他引:2
本文通过在华南四省区对四个野生种群猕猴声行为的观察和现场录音,对它们的叫声声学特性,行为模式和其它个体对其相应的行为反应进行了定量的分析研究,并得出11种不同的声行为,这些声行为有相互不同的声学特性,不同的行为模式并引起其它个体相应的行为反应,从而起着通讯的作用。叫声在猕猴的声行为通讯中,一些借助视觉提示,至少以不同的刺激度来“表示”某一类事物,并得到个体间的“共识”有些甚至无需视觉提示而单独传递 相似文献
160.
The polyamine-derived amino acid hypusine: its post-translational formation in eIF-5A and its role in cell proliferation 总被引:1,自引:0,他引:1
Myung Hee Park Young Ae Joe Kee Ryeon Kang Young Bok Lee Edith C. Wolff 《Amino acids》1996,10(2):109-121
Summary The unusual amino acid hypusine [N
-(4-amino-2-hydroxybutyl)lysine] is a unique component of one cellular protein, eukaryotic translation initiation factor 5A (eIF-5A, old terminology, eIF-4D). It is formed posttranslationally and exclusively in this protein in two consecutive enzymatic reactions, (i) modification of a single lysine residue of the eIF-5A precursor protein by the transfer of the 4-aminobutyl moiety of the polyamine spermidine to its-amino group to form the intermediate, deoxyhypusine [N
-(4-aminobutyl)lysine] and (ii) subsequent hydroxylation of this intermediate to form hypusine. The amino acid sequences surrounding the hypusine residue are strictly conserved in all eukaryotic species examined, suggesting the fundamental importance of this amino acid throughout evolution. Hypusine is required for the activity of eIF-5Ain vitro. There is strong evidence that hypusine and eIF-5A are vital for eukaryotic cell proliferation. Inactivation of both of the eIF-5A genes is lethal in yeast and the hypusine modification appears to be a requirement for yeast survival (Schnier et al., 1991 [Mol Cell Biol 11: 3105–3114]; Wöhl et al., 1993 [Mol Gen Genet 241: 305–311]). Furthermore, inhibitors of either of the hypusine biosynthetic enzymes, deoxyhypusine synthase or deoxyhypusine hydroxylase, exert strong anti-proliferative effects in mammalian cells, including many human cancer cell lines. These inhibitors hold potential as a new class of anticancer agents, targeting one specific eukaryotic cellular reaction, hypusine biosynthesis. 相似文献