A complete mitochondrial genome of wheat (Triticum aestivum cv. Chinese Yumai), and fast evolving mitochondrial genes in higher plants

Journal of genetics

Dongcheng Liu³  Guoyin Zhuo³  Songnian Hu²  Wenlong Yang³  Peng Cui²  Feng Ding²  Kehui Zhan¹  Jun Yu1²  Qiang Lin²  Aimin Zhang3³  Huitao Liu3³ 

[1] Agronomy College of Henan Agricultural University, Zhengzhou 450002, People’s Republic of China$$;The CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100029, People’s Republic of China$$;The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People’s Republic of China$$

关键词: wheat;    mitochondrial genome;    evolution;    relaxed selection.;   

DOI  :  

学科分类：生物科学（综合）

来源: Indian Academy of Sciences

【 摘 要 】

Plant mitochondrial genomes, encoding necessary proteins involved in the system of energy production, play an important role in the development and reproduction of the plant. They occupy a specific evolutionary pattern relative to their nuclear counterparts. Here, we determined the winter wheat (Triticum aestivum cv. Chinese Yumai) mitochondrial genome in a length of 452 and 526 bp by shotgun sequencing its BAC library. It contains 202 genes, including 35 known protein-coding genes, three rRNA and 17 tRNA genes, as well as 149 open reading frames (ORFs; greater than 300 bp in length). The sequence is almost identical to the previously reported sequence of the spring wheat (T. aestivum cv. Chinese Spring); we only identified seven SNPs (three transitions and four transversions) and 10 indels (insertions and deletions) between the two independently acquired sequences, and all variations were found in non-coding regions. This result confirmed the accuracy of the previously reported mitochondrial sequence of the Chinese Spring wheat. The nucleotide frequency and codon usage of wheat are common among the lineage of higher plant with a high AT-content of 58%. Molecular evolutionary analysis demonstrated that plant mitochondrial genomes evolved at different rates, which may correlate with substantial variations in metabolic rate and generation time among plant lineages. In addition, through the estimation of the ratio of non-synonymous to synonymous substitution rates between orthologous mitochondrion-encoded genes of higher plants, we found an accelerated evolutionary rate that seems to be the result of relaxed selection.

【 授权许可】

Unknown