Chen Z, Nie H, Grover C E, Wang Y, Li P, Wang M, Pei H, Zhao Y, Li S, Wendel J F, Hua J
Laboratory of Cotton Genetics, Genomics and Breeding, College of Agronomy and Biotechnology, Key Laboratory of Crop Heterosis and Utilization of Ministry of Education, Beijing Key Laboratory of Crop Genetic Improvement, China Agricultural University, Beijing, China.
Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, IA, USA.
Plant Biol (Stuttg). 2017 May;19(3):484-493. doi: 10.1111/plb.12536. Epub 2017 Feb 2.
Cotton (Gossypium spp.) is commonly grouped into eight diploid genomic groups, designated A-G and K, and an allotetraploid genomic group, AD. Gossypium raimondii (D ) and G. arboreum (A ) are the putative contributors to the progenitor of G. hirsutum (AD ), the economically important fibre-producing cotton species. Mitochondrial DNA from week-old etiolated seedlings was extracted from isolated organelles using discontinuous sucrose density gradient method. Mitochondrial genomes were sequenced, assembled, annotated and analysed in orderly. Gossypium raimondii (D ) and G. arboreum (A ) mitochondrial genomes were provided in this study. The mitochondrial genomes of two diploid species harboured circular genome of 643,914 bp (D ) and 687,482 bp (A ), respectively. They differ in size and number of repeat sequences, both contain illuminating triplicate sequences with 7317 and 10,246 bp, respectively, demonstrating dynamic difference and rearranged genome organisations. Comparing the D and A mitogenomes with mitogenomes of tetraploid Gossypium species (AD , G. hirsutum; AD , G. barbadense), a shared 11 kbp fragment loss was detected in allotetraploid species, three regions shared by G. arboreum (A ), G. hirsutum (AD ) and G. barbadense (AD ), while eight regions were specific to G. raimondii (D ). The presence/absence variations and gene-based phylogeny supported that A-genome is a cytoplasmic donor to the progenitor of allotetraploid species G. hirsutum and G. barbadense. The results present structure variations and phylogeny of Gossypium mitochondrial genome evolution.
棉花（棉属物种）通常分为八个二倍体基因组组，命名为A - G和K，以及一个异源四倍体基因组组AD。雷蒙德氏棉（D基因组）和亚洲棉（A基因组）被认为是陆地棉（AD基因组）——经济上重要的产纤维棉花物种——祖先的贡献者。使用不连续蔗糖密度梯度法从分离的细胞器中提取一周龄黄化幼苗的线粒体DNA。线粒体基因组按顺序进行测序、组装、注释和分析。本研究提供了雷蒙德氏棉（D基因组）和亚洲棉（A基因组）的线粒体基因组。两个二倍体物种的线粒体基因组分别含有643,914 bp（D基因组）和687,482 bp（A基因组）的环状基因组。它们在大小和重复序列数量上有所不同，两者分别包含长度为7317和10,246 bp的有启发性的三联体序列，表明存在动态差异和重排的基因组组织。将D基因组和A基因组的线粒体基因组与四倍体棉属物种（AD基因组，陆地棉；AD基因组，海岛棉）的线粒体基因组进行比较，在异源四倍体物种中检测到一个共享的11 kbp片段缺失，亚洲棉（A基因组）、陆地棉（AD基因组）和海岛棉（AD基因组）共有三个区域，而雷蒙德氏棉（D基因组）有八个特定区域。存在/缺失变异和基于基因的系统发育支持A基因组是异源四倍体物种陆地棉和海岛棉祖先的细胞质供体。结果展示了棉属线粒体基因组进化的结构变异和系统发育。
