Identification and comparative analysis of the chloroplast alpha-subunit gene of DNA-dependent RNA polymerase from seven Euglena species.
Identification and comparative analysis of the chloroplast alpha-subunit gene of DNA-dependent RNA polymerase from seven Euglena species.
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七种裸藻物种 DNA 依赖性 RNA 聚合酶叶绿体 α 亚基基因的鉴定和比较分析。
DOI：
10.1093/nar/30.5.1247
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发表时间：
2002
影响因子：
14.9
通讯作者：
Hallick,RichardB
中科院分区：
文献类型：
--
作者：
Sheveleva,ElenaV;Giordani,NicoleV;Hallick,RichardB
当1993年报道纤细眼虫叶绿体基因组序列时，根据所有推定的阅读框架与当时已知的rpoA位点的比较，RNA聚合酶的α亚基基因（rpoA）似乎缺失。由于已知的rpoA序列大量增加，因此重新研究了aEuglenachloroplastrpoA基因的问题。一个先前描述的未知的161个密码子的阅读框架被发现是由单个III组内含子分裂的anrpoA基因的一部分。该rpoA基因在不同的物种之间高度可变，然后在其他五种眼虫中分离和表征，Euglena anabaena，Euglena granulata，Euglena myxocylindracea，Euglena stellata和Euglena viridis，以及Astasia longaplastid基因组。所有七个EuglenarpoA基因都有一个或三个III组内含子。Euglenaspp.当与其他种类的细菌、藻类和植物中的therpoA基因相比时，似乎是该基因家族中最可变的。此外，EuglenarpoA蛋白缺乏与一些调节蛋白相互作用所需的C-末端结构域，这是仅与一些绿藻绿色藻类共享的特征。该基因是一个多基因簇的远端顺反子，该多基因簇包括碳水化合物生物合成、光合电子传递、天线复合体和核糖体蛋白基因。本研究为研究裸藻质体的转录系统、质体基因组的组织结构、III组内含子的进化和裸藻细胞的发生提供了新的视角。
When the sequence of theEuglena gracilischloroplast genome was reported in 1993 the α-subunit gene (rpoA) of RNA polymerase appeared to be missing, based on a comparison of all putative reading frames to the then knownrpoAloci. Since there has been a large increase in knownrpoAsequences, the question of aEuglenachloroplastrpoAgene was re-examined. A previously described unknown reading frame of 161 codons was found to be part of anrpoAgene split by a single group III intron. ThisrpoAgene, which is highly variable from species to species, was then isolated and characterized in five other euglenoid species,Euglena anabaena,Euglena granulata,Euglena myxocylindracea,Euglena stellataandEuglena viridis, and in theAstasia longaplastid genome. All sevenEuglenarpoAgenes have either one or three group III introns. TherpoAgene products inEuglenaspp. appear to be the most variable in this gene family when compared to therpoAgene in other species of bacteria, algae and plants. Additionally,EuglenarpoA proteins lack a C-terminal domain required for interaction with some regulatory proteins, a feature shared only with some chlorophyte green algae. TheE.gracilisrpoAgene is the distal cistron of a multigene cluster that includes genes for carbohydrate biosynthesis, photosynthetic electron transport, an antenna complex and ribosomal proteins. This study provides new insights into the transcription system of euglenoid plastids, the organization of the plastid genome, group III intron evolution and euglenoid phylogeny.