NAP-I is a functional homologue of TAP-I that is required for replication and transcription of the adenovirus genome in a chromatin-like structure
NAP-I is a functional homologue of TAP-I that is required for replication and transcription of the adenovirus genome in a chromatin-like structure
复制标题
DOI：
10.1046/j.1365-2443.1996.d01-223.x
复制
发表时间：
1996-12-01
期刊：
影响因子：
2.1
通讯作者：
Nagata, K
中科院分区：
文献类型：
--
作者：
Kawase, H;Okuwaki, M;Nagata, K
背景资料：为了从染色质结构中的DNA激活复制和转录，认为需要改变染色质结构的多种因子。模板激活因子-I（TAF-I）已被鉴定为与病毒碱性核心蛋白（Ad core）复合的腺病毒（Ad）基因组复制所需的宿主因子。TAF-I还刺激转录从广告核心DNA.Results：使用突变TAF-I蛋白质，我们已经证明，存在于羧基末端区域的酸性拉伸是必不可少的刺激转录从广告核心。用限制性内切酶进行的基因组足迹实验显示TAF-I引起Ad核心的结构变化。TAP-I与核小体组装蛋白-I（NAP-I）具有显著的氨基酸相似性，NAP-I参与染色质结构的形成。我们已经证明TAF-I可以被NAP-I取代来激活无细胞Ad核心转录系统。NAP-I的最大TAF-I活性需要NAP-I中的两个三联酸性区和与TAF-I同源的区域。此外，TAF-I已被证明具有NAP-I活性，并且TAP-I的酸性区域是这种activity.Conclusions所必需的：由于TAF-I引起Ad核心的结构变化，从而激活转录，TAF-I被认为是参与染色质重塑的蛋白质之一。NAP-I在结构上与TAF-I相关，并在功能上替代TAF-I。此外，TAF-I具有NAP-I活性。这些观察结果表明，这种类型的分子具有双重功能，可能通过参与促进染色质结构的组装以及扰乱染色质结构以允许转录进行。
Background: For the activation of replication and transcription from DNA in a chromatin structure, a variety of factors are thought to be needed that alter the chromatin structure. Template activating factor-I (TAF-I) has been identified as such a host factor required for replication of the adenovirus (Ad) genome complexed with viral basic core proteins (Ad core). TAF-I also stimulates transcription from the Ad core DNA.Results: Using mutant TAF-I proteins, we have demonstrated that the acidic stretch present in the carboxyl terminal region is essential for the stimulation of transcription from the Ad core. A genomic footprinting experiment with restriction endonuclease has revealed that TAF-I causes a structural change in the Ad core. TAP-I has been shown to have significant amino acid similarity to nucleosome assembly protein-I (NAP-I), which is involved in the formation of the chromatin structure. We have shown that TAF-I can be substituted by NAP-I in the activation of the cell-free Ad core transcription system. Two of the tripartite acidic regions and the region homologous to TAF-I in NAP-I are required for the maximal TAF-I activity of NAP-I. Furthermore, TAF-I has been shown to have NAP-I activity, and the acidic region of TAP-I is required for this activity.Conclusions: Since TAF-I causes the structural change of the Ad core and thereby activates transcription, TAF-I is thought to be one of the proteins which is involved in chromatin remodeling. NAP-I is structurally related to TAF-I and functionally substitutes for TAF-I. Furthermore, TAF-I has NAP-I activity. These observations suggest that this type of molecule has dual functions, possibly by participating in facilitating the assembly of the chromatin structure as well as perturbing the chromatin structure to allow transcription to proceed.