Pan Minhui, Yu Quanyou, Xia Yuling, Dai Fangyin, Liu Yanqun, Lu Cheng, Zhang Ze, Xiang Zhonghuai
Key Sericultural Laboratory of Agricultural Ministry, Southwest University, Chongqing 400716, China.
Sci China C Life Sci. 2008 Aug;51(8):693-701. doi: 10.1007/s11427-008-0097-6. Epub 2008 Aug 3.
The complete mitochondrial genome of Chinese Bombyx mandarina (ChBm) was determined. The circular genome is 15682 bp long, and contains a typical gene complement, order, and arrangement identical to that of Bombyx mori (B. mori) and Japanese Bombyx mandarina (JaBm) except for two additional tRNA-like structures: tRNA( Ser(TGA))-like and tRN( AIle(TAT))-like. All protein-coding sequences are initiated with a typical ATN codon except for the COI gene, which has a 4-bp TTAG putative initiator codon. Eleven of 13 protein-coding genes (PCGs) have a complete termination codon (all TAA), but the remaining two genes terminate with incomplete codons. All tRNAs have the typical clover-leaf structures of mitochondrial tRNAs, with the exception of tRNA( Ser(TGA))-like, with a four stem-and-loop structure. The length of the A+T-rich region of ChBm is 484 bp, shorter than those of JaBm (747 bp) and B. mori (494-499 bp). Phylogenetic analysis among B. mori, ChBm, JaBm, and Antheraea pernyi (Anpe) showed that B. mori is more closely related to ChBm than JaBm. The earliest divergence time estimate for B. mori-ChBm and B. mori-JaBm is about 1.08+/-0.18-1.41+/-0.24 and 1.53+/-0.20-2.01+/-0.26 Mya, respectively. ChBm and JaBm diverged around 1.11+/-0.16-1.45+/-0.21 Mya.
测定了中国野桑蚕（ChBm）的完整线粒体基因组。该环状基因组长度为15682 bp，除了两个额外的类似tRNA的结构：类似tRNA(Ser(TGA))和类似tRN(AIle(TAT))外，其基因组成、顺序和排列与家蚕（B. mori）和日本野桑蚕（JaBm）的典型情况相同。除了COI基因起始密码子为4个碱基的TTAG推测起始密码子外，所有蛋白质编码序列均以典型的ATN密码子起始。13个蛋白质编码基因（PCGs）中有11个具有完整的终止密码子（均为TAA），但其余两个基因以不完整密码子终止。所有tRNA都具有线粒体tRNA典型的三叶草结构，除了类似tRNA(Ser(TGA))具有四叶草结构。ChBm的富含A+T区域长度为484 bp，短于JaBm（747 bp）和家蚕（494 - 499 bp）。家蚕、ChBm、JaBm和柞蚕（Anpe）之间的系统发育分析表明，家蚕与ChBm的亲缘关系比与JaBm更近。家蚕 - ChBm和家蚕 - JaBm的最早分歧时间估计分别约为1.08±0.18 - 1.41±0.24和1.53±0.20 - 2.01±0.26百万年前。ChBm和JaBm在约1.11±0.16 - 1.45±0.21百万年前分歧。
