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21.
A.J. van Agthoven J.A. Maassen P.I. Schrier W. Mo¨ller 《Biochemical and biophysical research communications》1975,64(4):1184-1191
The E. coli ribosomal proteins L12 and its N-acetylated form L7 were cleaved into an N-terminal and C-terminal fragment of roughly comparable size. The selective cleavage at the lone arginine residue was accomplished by trypsin treatment of the citraconylated proteins, followed by removal of the citraconyl moieties. These fragments, both separately and in combination, were incapable of reconstituting elongation factor G (EF-G) dependent GTPase of CsCl ribosomal cores supplemented with L10. However, incubation of cores containing L10 with the N-terminal fragment prevented the reconstitution of GTPase activity by intact L7/L12. No inhibition was observed when CsCl cores lacking L10 were incubated with the N-terminal fragment followed by addition of a preincubated mixture of L7/L12 and L10. The results indicate that the N-terminal part of L7/L12 is responsible for its ability to bind to 50S ribosomes and that L7/L12 together with L10 form a protein cluster on the ribosome. 相似文献
22.
Bunyavirus ribonucleoprotein (RNP) that is assembled by polymerized nucleoproteins (N) coating a viral RNA and associating with a viral polymerase can be both the RNA synthesis machinery and the structural core of virions. Bunyaviral N and RNP thus could be assailable targets for host antiviral defense; however, it remains unclear which and how host factors target N/RNP to restrict bunyaviral infection. By mass spectrometry and protein-interaction analyses, we here show that host protein MOV10 targets the N proteins encoded by a group of emerging high-pathogenic representatives of bunyaviruses including severe fever with thrombocytopenia syndrome virus (SFTSV), one of the most dangerous pathogens listed by World Health Organization, in RNA-independent manner. MOV10 that was further shown to be induced specifically by SFTSV and related bunyaviruses in turn inhibits the bunyaviral replication in infected cells in series of loss/gain-of-function assays. Moreover, animal infection experiments with MOV10 knockdown corroborated the role of MOV10 in restricting SFTSV infection and pathogenicity in vivo. Minigenome assays and additional functional and mechanistic investigations demonstrate that the anti-bunyavirus activity of MOV10 is likely achieved by direct impact on viral RNP machinery but independent of its helicase activity and the cellular interferon pathway. Indeed, by its N-terminus, MOV10 binds to a protruding N-arm domain of N consisting of only 34 amino acids but proving important for N function and blocks N polymerization, N-RNA binding, and N-polymerase interaction, disabling RNP assembly. This study not only advances the understanding of bunyaviral replication and host restriction mechanisms but also presents novel paradigms for both direct antiviral action of MOV10 and host targeting of viral RNP machinery. 相似文献
23.
Zhisheng Zhang Delin Mo Peiqing Cong Zuyong He Fei Ling Anning Li Yuna Niu Xiao Zhao Chunyan Zhou Yaosheng Chen 《Molecular biology reports》2010,37(3):1611-1618
The product of transmembrane and coiled-coil domains 1 (TMCO1) gene is a member of DUF841 superfamily of several eukaryotic proteins with unknown function. The partial DNA sequence of
porcine TMCO1 was first cloned with a pig 567 bp ORF encoding 188 amino acids. By tissues expression analysis, the TMCO1 was found highly expressed in the liver, kidney and heart. The porcine TMCO1 protein was subsequently demonstrated to localize
in the mitochondrion by confocal fluorescence microscopy. This data provides an important basis for conducing further studies
on the functions and regulatory mechanisms underlying the role of TMCO1 gene. 相似文献
24.
J Zhang P Hellwig J P Osborne H W Huang P Mo?nne-Loccoz A A Konstantinov R B Gennis 《Biochemistry》2001,40(29):8548-8556
Cytochrome bd is one of the two quinol oxidases in the respiratory chain of Escherichia coli. The enzyme contains three heme prosthetic groups. The dioxygen binding site is heme d, which is thought to be part of the heme-heme binuclear center along with heme b(595), which is a high-spin heme whose function is not known. Protein sequence alignments [Osborne, J. P., and Gennis, R. B. (1999) Biochim. Biophys Acta 1410, 32--50] of cytochrome bd quinol oxidase sequences from different microorganisms have revealed a highly conserved sequence (GWXXXEXGRQPW; bold letters indicate strictly conserved residues) predicted to be on the periplasmic side of the membrane between transmembrane helices 8 and 9 in subunit I. The functional importance of this region is investigated in the current work by site-directed mutagenesis. Several mutations in this region (W441A, E445A/Q, R448A, Q449A, and W451A) resulted in a catalytically inactive enzyme with abnormal UV--vis spectra. E445A was selected for detailed analysis because of the absence of the absorption bands from heme b(595). Detailed spectroscopic and chemical analyses, indeed, show that one of the three heme prosthetic groups in the enzyme, heme b(595), is specifically perturbed and mostly missing from this mutant. Surprisingly, heme d, while known to interact with heme b(595), appears relatively unperturbed, whereas the low-spin heme b(558) shows some modification. This is the first report of a mutation that specifically affects the binding site of heme b(595). 相似文献
25.
Bohong Liao Lingrong Peng Jin Zhou Huiting Mo Jialan Zhao Zike Yang Xiaowen Guo Peiquan Zhang Xin Zhang Zhibo Zhu 《化学与生物多样性》2019,16(5)
Human nasopharyngeal carcinoma is a common head and neck malignancy with high incidence in Southeast Asia and Southern China. It is necessary to develop safe, effective and inexpensive anticancer agents to improve the therapeutics of patients with nasopharyngeal carcinoma. A series of small molecular compounds based on 6‐(pyrimidin‐4‐yl)‐1H‐indazole were synthesized and evaluated for antiproliferative activities against human nasopharyngeal carcinoma cell lines SUNE1. Compounds 6b , 6c , 6e and 6l showed potent antiproliferative activities similar to positive control drug cisplatin in vitro with lower nephrotoxicity than it. N‐[4‐(1H‐Indazol‐6‐yl)pyrimidin‐2‐yl]benzene‐1,3‐diamine ( 6l ) was selected for further study. It was found that 6l induced mitochondria‐mediated apoptosis and G2/M phase arrest in SUNE1 cells. Furthermore, compound 6l at 10 mg/kg can suppress the growth of an implanted SUNE1 xenograft with a TGI% (tumor growth inhibition) value of 50 % and did not cause serious side effects in BALB/c nude mice. This study suggests that 6‐(pyrimidin‐4‐yl)‐1H‐indazole derivatives are a series of small molecule compounds with anti‐nasopharyngeal carcinoma activities. 相似文献
26.
27.
A. H. Jelle Loonstra Mo A. Verhoeven Nathan R. Senner Christiaan Both Theunis Piersma 《Ecology letters》2019,22(12):2060-2066
Long‐distance migratory flights are predicted to be associated with higher mortality rates when individuals encounter adverse weather conditions. However, directly connecting environmental conditions experienced in‐flight with the survival of migrants has proven difficult. We studied how the in‐flight mortality of 53 satellite‐tagged Black‐tailed Godwits (Limosa limosa limosa) during 132 crossings of the Sahara Desert, a major geographical barrier along their migration route between The Netherlands and sub‐Saharan Africa, is correlated with the experienced wind conditions and departure date during both southward and northward migration. We show that godwits experienced higher wind assistance during southward crossings, which seems to reflect local prevailing trade winds. Critically, we found that fatal northward crossings (15 deaths during 61 crossings) were associated with adverse wind conditions. Wind conditions during migration can thus directly influence vital rates. Changing wind conditions associated with global change may thus profoundly influence the costs of long‐distance migration in the future. 相似文献
28.
Jun Zhang Kevin A. Fengler John L. Van Hemert Rajeev Gupta Nick Mongar Jindong Sun William B. Allen Yang Wang Benjamin Weers Hua Mo Renee Lafitte Zhenglin Hou Angela Bryant Farag Ibraheem Jennifer Arp Kankshita Swaminathan Stephen P. Moose Bailin Li Bo Shen 《Plant biotechnology journal》2019,17(12):2272-2285
29.
Xingfeng He Qiang Bai Yunsheng Liu Adelaide M. Nolan Chen Ling Yifei Mo 《Liver Transplantation》2019,9(43)
As technologically important materials for solid‐state batteries, Li super‐ionic conductors are a class of materials exhibiting exceptionally high ionic conductivity at room temperature. These materials have unique crystal structural frameworks hosting a highly conductive Li sublattice. However, it is not understood why certain crystal structures of the super‐ionic conductors lead to high conductivity in the Li sublattice. In this study, using topological analysis and ab initio molecular dynamics simulations, the crystal structures of all Li‐conducting oxides and sulfides are studied systematically and the key features pertaining to fast‐ion conduction are quantified. In particular, a unique feature of enlarged Li sites caused by large local spaces in the crystal structural framework is identified, promoting fast conduction in the Li‐ion sublattice. Based on these quantified features, the high‐throughput screening identifies many new structures as fast Li‐ion conductors, which are further confirmed by ab initio molecular dynamics simulations. This study provides new insights and a systematic quantitative understanding of the crystal structural frameworks of fast ion‐conductor materials and motivates future experimental and computational studies on new fast‐ion conductors. 相似文献
30.
水稻稻瘟病抗性基因的克隆、育种利用及稻瘟菌无毒基因研究进展 总被引:2,自引:0,他引:2
稻瘟病是世界上影响水稻(Oryza sativa)粮食生产的主要病害之一, 抗病基因的发掘与利用是抗病育种的基础和核心。随着寄主水稻和病原菌稻瘟病菌(Magnaporthe oryzae)基因组测序和基因注释的完成, 水稻和稻瘟病菌的互作体系成为研究植物与真菌互作的模式系统。该文对稻瘟病抗病基因的遗传、定位、克隆及育种利用进行概述, 并通过生物信息学分析方法, 探讨了水稻全基因组中NBS-LRR类抗病基因在水稻12条染色体上的分布情况, 同时对稻瘟病菌无毒基因的鉴定及无毒蛋白与抗病蛋白的互作进行初步分析。最后对稻瘟病抗病基因研究存在的问题进行分析并展望了未来的研究方向, 以期为水稻抗稻瘟病育种发展和抗病机制的深入理解提供参考。 相似文献