Sequence of the Gonium pectorale Mating Locus Reveals a Complex and Dynamic History of Changes in Volvocine Algal Mating Haplotypes.
Sequence of the Gonium pectorale Mating Locus Reveals a Complex and Dynamic History of Changes in Volvocine Algal Mating Haplotypes.
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贡果酱交配基因座的序列揭示了Volvocine Algal交配单倍型变化的复杂而动态的历史。
DOI：
10.1534/g3.115.026229
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发表时间：
2016-05-03
期刊：
影响因子：
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通讯作者：
Nozaki H
中科院分区：
文献类型：
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作者：
Hamaji T;Mogi Y;Ferris PJ;Mori T;Miyagishima S;Kabeya Y;Nishimura Y;Toyoda A;Noguchi H;Fujiyama A;Olson BJ;Marriage TN;Nishii I;Umen JG;Nozaki H
在莱茵衣藻（Chlamydomonas reinhardtii）和卡蒂衣藻（Volvox carteri）这两种已测序的涡藻物种中，性别决定区（sdr）或交配型（MT）位点在大小、结构、基因含量和配子学分化方面存在重大差异。了解这些差异的起源需要对相关物种的MT位点进行调查。在这里，我们确定了与多细胞V. carteri的关系比与C. reinhardtii更密切的16细胞角藻（Gonium pectorale）负MT和正MT单倍型的序列。相比于莱茵哈蒂木，胸叶木的大小稍大，结构较不复杂，只有两个共线配子学的主要共系区。但是，胸胸草的配子学内容与V. carteri的重叠多于与C. reinhardtii的重叠，而胸胸草配子学的等位基因差异甚至低于C. reinhardtii。三种关键的性别相关基因在胸凤梨MT中保守：MT -中的GpMID和GpMTD1， MT+中的GpFUS1。GpFUS1蛋白在正配子交配结构中表现出特异性定位，表明其在受精中具有保守功能。我们的研究结果表明，G. pectorale-V。carteri共同祖先MT在与c.l inhardtii分离后至少经历了一次重大的重组，并且carteri共同祖先MT在与g.p ectorale分离后经历了随后的扩张和重组丧失。这些数据开始分化volvoline MT基因座中发生的重要变化，并突出了sdr中不连续和动态演变的潜力。
Sex-determining regions (SDRs) or mating-type (MT) loci in two sequenced volvocine algal species, Chlamydomonas reinhardtii and Volvox carteri, exhibit major differences in size, structure, gene content, and gametolog differentiation. Understanding the origin of these differences requires investigation of MT loci from related species. Here, we determined the sequences of the minus and plus MT haplotypes of the isogamous 16-celled volvocine alga, Gonium pectorale, which is more closely related to the multicellular V. carteri than to C. reinhardtii. Compared to C. reinhardtii MT, G. pectorale MT is moderately larger in size, and has a less complex structure, with only two major syntenic blocs of collinear gametologs. However, the gametolog content of G. pectorale MT has more overlap with that of V. carteri MT than with C. reinhardtii MT, while the allelic divergence between gametologs in G. pectorale is even lower than that in C. reinhardtii. Three key sex-related genes are conserved in G. pectorale MT: GpMID and GpMTD1 in MT–, and GpFUS1 in MT+. GpFUS1 protein exhibited specific localization at the plus-gametic mating structure, indicating a conserved function in fertilization. Our results suggest that the G. pectorale–V. carteri common ancestral MT experienced at least one major reformation after the split from C. reinhardtii, and that the V. carteri ancestral MT underwent a subsequent expansion and loss of recombination after the divergence from G. pectorale. These data begin to polarize important changes that occurred in volvocine MT loci, and highlight the potential for discontinuous and dynamic evolution in SDRs.