Function of plastid sigma factors in higher plants: regulation of gene expression or just preservation of constitutive transcription?
Function of plastid sigma factors in higher plants: regulation of gene expression or just preservation of constitutive transcription?
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DOI：
10.1007/s11103-010-9714-4
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发表时间：
2011-07-01
影响因子：
5.1
通讯作者：
Lerbs-Mache, Silva
中科院分区：
文献类型：
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作者：
Lerbs-Mache, Silva
质体基因的表达是相当复杂的。转录由三种不同的RNA聚合酶进行，其中两种是噬菌体型的核编码的单体（称为RPOTp和RPOTMP），其中一种是真细菌型的质体编码的多聚体（称为PEP）。真细菌型RNA聚合酶的活性受多达六个核编码的σ型转录起始因子调节。质体转录装置的这种复杂性尚未得到很好的理解，并提出了一个问题，即它是否受到任何调控或只是确保质体基因组的组成型转录。另一方面，在过去的几年里，已经取得了相当大的进展，阐明了特异性启动子识别和一些质体基因的选择性转录的西格玛因子的作用。西格玛相互作用蛋白质已被鉴定出来，西格玛因子的磷酸化依赖性功能变化也已被揭示。本综述旨在总结这些最新的进展，并说服读者，质体基因的表达是在转录水平上的sigma因子的作用。
Plastid gene expression is rather complex. Transcription is performed by three different RNA polymerases, two of them are nucleus-encoded, monomeric, of the phage-type (named RPOTp and RPOTmp) and one of them is plastid-encoded, multimeric, of the eubacterial-type (named PEP). The activity of the eubacterial-type RNA polymerase is regulated by up to six nucleus-encoded transcription initiation factors of the sigma-type. This complexity of the plastid transcriptional apparatus is not yet well understood and raises the question of whether it is subject to any regulation or just ensures constitutive transcription of the plastid genome. On the other hand, considerable advances have been made during the last years elucidating the role of sigma factors for specific promoter recognition and selected transcription of some plastid genes. Sigma-interacting proteins have been identified and phosphorylation-dependent functional changes of sigma factors have been revealed. The present review aims to summarize these recent advances and to convince the reader that plastid gene expression is regulated on the transcriptional level by sigma factor action.