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641.
642.
Umair Khan Prajwalini Mehere Senthilkumar Deivasigamani Girish S. Ratnaparkhi 《Genesis (New York, N.Y. : 2000)》2013,51(9):619-629
SUMO is a protein posttranslational modifier. SUMO cycle components are believed to be conserved in all eukaryotes. Proteomic analyses have lead to the identification a wealth of SUMO targets that are involved in almost every cellular function in eukaryotes. In this article, we describe the characterization of SUMO Cycle components in Hydra, a Cnidarian with an ability to regenerate body parts. In cells, the translated SUMO polypeptide cannot conjugate to a substrate protein unless the C‐terminal tail is cleaved, exposing the di‐Glycine motif. This critical task is done by SUMO proteases that in addition to SUMO maturation are also involved in deconjugating SUMO from its substrate. We describe the identification, bioinformatics analysis, cloning, and biochemical characterization of Hydra SUMO cycle components, with a focus on SUMO and SUMO proteases. We demonstrate that the ability of SUMO proteases to process immature SUMO is conserved from Hydra to flies. A transgenic Hydra, expressing a SUMO‐GFP fusion protein under a constitutive actin promoter, is generated in an attempt to monitor the SUMO Cycle in vivo as also to purify and identify SUMO targets in Hydra. genesis 51:619–629. © 2013 Wiley Periodicals, Inc. 相似文献
643.
The effects of kinship and density on growth and metamorphosis of the bronze frog (Rana
temporalis) tadpoles 总被引:1,自引:0,他引:1
Five clutches of Rana
temporalis eggs collected along a stream were reared separately until formation of Gosner stage 25 tadpoles. The effect of kinship and
density was then studied by rearing ten siblings in 1 (sib 1) or 5 (sib 5) l water, and mixed rearing of ten tadpoles (2 from
each of the 5 clutches) in 1 (mix 1) or 5 (mix 5) l water; each group replicated five times. In all the groups tadpoles showed
a sigmoid growth curve. Both kinship and density interacted to affect mean proportions of individuals reaching metamorphic
climax (MC), mean body mass, and size frequency at MC (day 79). The proportion of tadpoles reaching MC was highest in sib
5 (82%) followed by mix 5 (77%), sib 1 (73%), and mix 1 (64%) groups. Crowding plus mixing significantly lowered the median
developmental stage mean body mass and broadened the spectrum of developmental stages or size classes at MC. The size difference
of individuals at MC was inversely related to density of rearing. Frequency of different developmental stages was comparable
in sib 1, sib 5, and mix 5 groups. Interestingly, small individuals were significantly greater in number in the mix 1 group
compared to sib 1. The above findings suggest that genotypic heterogeneity in conjunction with crowding retards growth rate
of tadpoles in comparison with those reared in a genetically homogenous (sib) environment. Further, they suggest that the
adverse effect of mixed rearing is context dependent.
Received: 12 April 1999 / Received in revised form: 16 June 1999 / Accepted: 18 June 1999 相似文献
644.
645.
Girish G. Ariga Praveen N. Naik Sharanappa T. Nandibewoor 《Journal of biomolecular structure & dynamics》2017,35(14):3161-3175
The goal of this study was to investigate the interactions between meclizine (MEC) and human serum albumin (HSA) under physiological conditions by different spectroscopies and molecular modeling technique. The drug, MEC quenched the intrinsic fluorescence of HSA and the analysis of the results revealed that static quenching mechanism. The binding of MEC quenches the HSA fluorescence; stoichiometry was 1:1 interaction. Thermodynamic quantities were calculated at different temperatures suggested that hydrophobic and van der Waals interaction with HSA–MEC. The molecular distance, r, between donor and acceptor was estimated according to Forster’s theory of non-radiation energy transfer. CD and FT-IR studies confirm changes of secondary structure of HSA. Molecular docking studies validate MEC molecule interact to HSA in sub domain IIA. 相似文献
646.
T. L. Braber A. Mosterd N. H. J. Prakken P. A. F. M. Doevendans W. P. Th. M. Mali F. J. G. Backx D. E. Grobbee R. Rienks H. M. Nathoe M. L. Bots B. K. Velthuis 《Netherlands heart journal》2015,23(2):133-138
BackgroundMore than 90 % of exercise-related cardiac arrests occur in men, predominantly those aged 45 years and older with coronary artery disease (CAD) as the main cause. The current sports medical evaluation (SME) of middle-aged recreational athletes consists of a medical history, physical examination, and resting and exercise electrocardiography. Coronary CT (CCT) provides a minimally invasive low radiation dose opportunity to image the coronary arteries. We present the study protocol of the Measuring Athlete’s Risk of Cardiovascular events (MARC) study. MARC aims to assess the additional value of CCT to a routine SME in asymptomatic sportsmen ≥45 years without known CAD.DesignMARC is a prospective study of 300 asymptomatic sportsmen ≥45 years who will undergo CCT if the SME does not reveal any cardiac abnormalities. The prevalence and determinants of CAD (coronary artery calcium score ≥100 Agatston Units (AU) or ≥50 % luminal stenosis) will be reported. The number needed to screen to prevent the occurrence of one cardiovascular event in the next 5 years, conditional to adequate treatment, will be estimated.DiscussionWe aim to determine the prevalence and severity of CAD and the additional value of CCT in asymptomatic middle-aged (≥45 years) sportsmen whose routine SME revealed no cardiac abnormalities.
Electronic supplementary material
The online version of this article (doi:10.1007/s12471-014-0630-0) contains supplementary material, which is available to authorized users. 相似文献647.
648.
Comprehensive Analysis of Varicella-Zoster Virus Proteins Using a New Monoclonal Antibody Collection
Tihana Lenac Rovi? Susanne M. Bailer Venkata R. Pothineni Werner J. D. Ouwendijk Hrvoje ?imi? Marina Babi? Karmela Mikli? Suzana Mali? Marieke C. Verweij Armin Baiker Orland Gonzalez Albrecht von Brunn Ralf Zimmer Klaus Früh Georges M. G. M. Verjans Stipan Jonji? Jürgen Haas 《Journal of virology》2013,87(12):6943-6954
Varicella-zoster virus (VZV) is the etiological agent of chickenpox and shingles. Due to the virus''s restricted host and cell type tropism and the lack of tools for VZV proteomics, it is one of the least-characterized human herpesviruses. We generated 251 monoclonal antibodies (MAbs) against 59 of the 71 (83%) currently known unique VZV proteins to characterize VZV protein expression in vitro and in situ. Using this new set of MAbs, 44 viral proteins were detected by Western blotting (WB) and indirect immunofluorescence (IF); 13 were detected by WB only, and 2 were detected by IF only. A large proportion of viral proteins was analyzed for the first time in the context of virus infection. Our study revealed the subcellular localization of 46 proteins, 14 of which were analyzed in detail by confocal microscopy. Seven viral proteins were analyzed in time course experiments and showed a cascade-like temporal gene expression pattern similar to those of other herpesviruses. Furthermore, selected MAbs tested positive on human skin lesions by using immunohistochemistry, demonstrating the wide applicability of the MAb collection. Finally, a significant portion of the VZV-specific antibodies reacted with orthologs of simian varicella virus (SVV), thus enabling the systematic analysis of varicella in a nonhuman primate model system. In summary, this study provides insight into the potential function of numerous VZV proteins and novel tools to systematically study VZV and SVV pathogenesis. 相似文献