Kostrzewa M, Zetsche K
Institut für Pflanzenphysiologie, Justus-Liebig-Universität, Giessen, Germany.
J Mol Biol. 1992 Oct 5;227(3):961-70. doi: 10.1016/0022-2836(92)90238-f.
The large plastid ATP synthase operon of the multicellular red alga Antithamnion sp. was cloned and the sequence of six ATPase genes determined. The operon resembles more the one from cyanobacteria than the ATP synthase operon of the chloroplast genome. The gene order is atpI, H, G, F, D and A, coding for the ATPase subunits a, c, b', b, delta and alpha, respectively. In green plants, the genes atpG and atpD are located in the nucleus. Unlike the situation in three published cyanobacterial ATP synthase operons, atpC, coding for the gamma subunit, is not a part of the rhodoplast operon. A single 4.5 kb transcript was detected with atpG, F, D and A gene probes that could span the whole operon, but no transcript could be detected with atpI and atpH probes. The end of an open reading frame preceding the atp genes shows remarkable homology to elongation factor TS from Escherichia coli. Behind the ATPase cluster, two open reading frames were detected that are not homologous to any known chloroplast gene. One of them may code for a transport protein of unknown specificity. Gene arrangement and sequence comparisons support the hypothesis of a polyphyletic origin of rhodoplasts and chloroplasts.
对多细胞红藻Antithamnion sp.的大型质体ATP合酶操纵子进行了克隆，并测定了6个ATP酶基因的序列。该操纵子与蓝细菌的操纵子更为相似，而非叶绿体基因组的ATP合酶操纵子。基因顺序为atpI、H、G、F、D和A，分别编码ATP酶亚基a、c、b'、b、δ和α。在绿色植物中，atpG和atpD基因位于细胞核中。与已发表的三个蓝细菌ATP合酶操纵子的情况不同，编码γ亚基的atpC不是红藻质体操纵子的一部分。用atpG、F、D和A基因探针检测到一个单一的4.5 kb转录本，它可能跨越整个操纵子，但用atpI和atpH探针未检测到转录本。atp基因之前的一个开放阅读框的末端与大肠杆菌的延伸因子TS具有显著的同源性。在ATP酶簇之后，检测到两个开放阅读框，它们与任何已知的叶绿体基因都没有同源性。其中一个可能编码一种特异性未知的转运蛋白。基因排列和序列比较支持红藻质体和叶绿体多系起源的假说。
