PDF(Pubmed)
Abstract：
BACKGROUND: China is the hotspot of global freshwater crab diversity, but their wild populations are facing severe pressures associated with anthropogenic factors, necessitating the need to map their taxonomic and genetic diversity and design conservation policies.
RESULTS: Herein, we sequenced the mitochondrial genome of a Chinese freshwater crab species Bottapotamon fukienense, and found that it is fragmented into two chromosomes. We confirmed that fragmentation was not limited to a single specimen or population. Chromosome 1 comprised 15,111 base pairs (bp) and there were 26 genes and one pseudogene (pseudo-nad1) encoded on it. Chromosome 2 comprised 8,173 bp and there were 12 genes and two pseudogenes (pseudo-trnL2 and pseudo-rrnL) encoded on it. Combined, they comprise the largest mitogenome (23,284 bp) among the Potamidae. Bottapotamon was the only genus in the Potamidae dataset exhibiting rearrangements of protein-coding genes. Bottapotamon fukienense exhibited average rates of sequence evolution in the dataset and did not differ in selection pressures from the remaining Potamidae.
CONCLUSIONS: This is the first experimentally confirmed fragmentation of a mitogenome in crustaceans. While the mitogenome of B. fukienense exhibited multiple signs of elevated mitogenomic architecture evolution rates, including the exceptionally large size, duplicated genes, pseudogenisation, rearrangements of protein-coding genes, and fragmentation, there is no evidence that this is matched by elevated sequence evolutionary rates or changes in selection pressures.
RESULTS: Herein, we sequenced the mitochondrial genome of a Chinese freshwater crab species Bottapotamon fukienense, and found that it is fragmented into two chromosomes. We confirmed that fragmentation was not limited to a single specimen or population. Chromosome 1 comprised 15,111 base pairs (bp) and there were 26 genes and one pseudogene (pseudo-nad1) encoded on it. Chromosome 2 comprised 8,173 bp and there were 12 genes and two pseudogenes (pseudo-trnL2 and pseudo-rrnL) encoded on it. Combined, they comprise the largest mitogenome (23,284 bp) among the Potamidae. Bottapotamon was the only genus in the Potamidae dataset exhibiting rearrangements of protein-coding genes. Bottapotamon fukienense exhibited average rates of sequence evolution in the dataset and did not differ in selection pressures from the remaining Potamidae.
CONCLUSIONS: This is the first experimentally confirmed fragmentation of a mitogenome in crustaceans. While the mitogenome of B. fukienense exhibited multiple signs of elevated mitogenomic architecture evolution rates, including the exceptionally large size, duplicated genes, pseudogenisation, rearrangements of protein-coding genes, and fragmentation, there is no evidence that this is matched by elevated sequence evolutionary rates or changes in selection pressures.
摘要：
背景:中国是全球淡水蟹多样性研究的热点,但是他们的野生种群面临着与人为因素相关的严重压力，有必要绘制其分类和遗传多样性图，并设计保护政策。
结果：这里，我们对一种中国淡水蟹的线粒体基因组进行了测序，发现它被分成两条染色体。我们证实碎片化不限于单个标本或群体。1号染色体包含15,111个碱基对（bp），在其上编码26个基因和一个假基因（伪nad1）。2号染色体包含8,173bp，在其上编码12个基因和两个假基因（伪trnL2和伪rrnL）。合并,它们是Potamidae中最大的有丝分裂体（23,284bp）。Bottapotamon是Potamiae数据集中唯一显示蛋白质编码基因重排的属。Bottapotamonfukienense在数据集中表现出平均序列进化率，并且与其余的Potamidae在选择压力上没有差异。
结论：这是甲壳类动物中第一个经实验证实的有丝分裂体的分裂。而福氏芽孢杆菌的有丝分裂基因组表现出多种有丝分裂基因组结构进化速率升高的迹象，包括特别大的尺寸，重复的基因，伪生殖，蛋白质编码基因的重排，和碎片化，没有证据表明这与升高的序列进化率或选择压力的变化相匹配.
结果：这里，我们对一种中国淡水蟹的线粒体基因组进行了测序，发现它被分成两条染色体。我们证实碎片化不限于单个标本或群体。1号染色体包含15,111个碱基对（bp），在其上编码26个基因和一个假基因（伪nad1）。2号染色体包含8,173bp，在其上编码12个基因和两个假基因（伪trnL2和伪rrnL）。合并,它们是Potamidae中最大的有丝分裂体（23,284bp）。Bottapotamon是Potamiae数据集中唯一显示蛋白质编码基因重排的属。Bottapotamonfukienense在数据集中表现出平均序列进化率，并且与其余的Potamidae在选择压力上没有差异。
结论：这是甲壳类动物中第一个经实验证实的有丝分裂体的分裂。而福氏芽孢杆菌的有丝分裂基因组表现出多种有丝分裂基因组结构进化速率升高的迹象，包括特别大的尺寸，重复的基因，伪生殖，蛋白质编码基因的重排，和碎片化，没有证据表明这与升高的序列进化率或选择压力的变化相匹配.
