Hunt D M
Department of Microbiology and Immunology, University of South Carolina School of Medicine, Columbia 29208.
J Gen Virol. 1989 Mar;70 ( Pt 3):535-42. doi: 10.1099/0022-1317-70-3-535.
Other workers have reported that vesicular stomatitis virus makes aberrantly long polyadenylic acid [poly(A)] tracts in the presence of S-adenosylhomocysteine (S-Ado-Hcy). In the work reported in this paper, the effects of various analogues of S-adenosylmethionine (S-Ado-Met) and ATP on polyadenylation in an in vitro transcription system were examined to determine whether S-Ado-Hcy exerted its effect on polyadenylation due to its relationship to S-Ado-Met or to ATP. It appeared that compounds which affected polyadenylation were those which were closely related to S-Ado-Met and that had the same L-aminoacyl side chain [(COOH)-CH(NH)2-CH2-CH2-]; the nature of the substituent at the -S+(CH3)- position of S-Ado-Met was less important. These analogues appeared to compete with S-Ado-Met for a binding site(s). These data support a model whereby compounds binding at an S-Ado-Met-binding site may have allosteric effects by causing or preventing conformational changes which are involved in polyadenylation reactions, perhaps by affecting the rate of polyadenylation or of termination.
其他研究人员报告称，在存在S-腺苷同型半胱氨酸（S-Ado-Hcy）的情况下，水疱性口炎病毒会产生异常长的聚腺苷酸[poly(A)]链。在本文报道的研究中，研究了S-腺苷甲硫氨酸（S-Ado-Met）和ATP的各种类似物对体外转录系统中聚腺苷酸化的影响，以确定S-Ado-Hcy对聚腺苷酸化的影响是由于其与S-Ado-Met的关系还是与ATP的关系。结果表明，影响聚腺苷酸化的化合物是那些与S-Ado-Met密切相关且具有相同L-氨酰基侧链[（COOH）-CH（NH）2-CH2-CH2-]的化合物；S-Ado-Met的-S+(CH3)-位置上取代基的性质不太重要。这些类似物似乎与S-Ado-Met竞争一个结合位点。这些数据支持了一个模型，即结合在S-Ado-Met结合位点的化合物可能通过引起或阻止参与聚腺苷酸化反应的构象变化而产生变构效应，这可能是通过影响聚腺苷酸化或终止的速率来实现的。
