Zhu Zuobin, Lu Qing, Zeng Fangfang, Wang Junjing, Huang Shi
State Key Laboratory of Medical Genetics, School of Life Sciences, Xiangya Medical School, Central South University, 110 Xiangya Road, Changsha, Hunan, 410078, China.
Sci Rep. 2015 Nov 25;5:17303. doi: 10.1038/srep17303.
Mutations in mitochondrial genome have epistatic effects on organisms depending on the nuclear background, but a role for the compatibility of mitochondrial-nuclear genomes (mit-n) in the quantitative nature of a complex trait remains unexplored. We studied a panel of recombinant inbred advanced intercrossed lines (RIAILs) of C. elegans that were established from a cross between the N2 and HW strains. We determined the HW nuclear genome content and the mitochondrial type (HW or N2) of each RIAIL strain. We found that the degree of mit-n compatibility was correlated with the lifespans but not the foraging behaviors of RIAILs. Several known aging-associated QTLs individually showed no relationship with mitotypes but collectively a weak trend consistent with a role in mit-n compatibility. By association mapping, we identified 293 SNPs that showed linkage with lifespan and a relationship with mitotypes consistent with a role in mit-n compatibility. We further found an association between mit-n compatibility and several functional characteristics of mitochondria as well as the expressions of genes involved in the respiratory oxidation pathway. The results provide the first evidence implicating mit-n compatibility in the quantitative nature of a complex trait, and may be informative to certain evolutionary puzzles on hybrids.
线粒体基因组中的突变对生物体具有上位性效应，具体取决于核背景，但线粒体-核基因组（mit-n）的兼容性在复杂性状的数量特征中的作用仍未得到探索。我们研究了一组从N2和HW品系杂交建立的秀丽隐杆线虫重组近交高级杂交系（RIAILs）。我们确定了每个RIAIL品系的HW核基因组含量和线粒体类型（HW或N2）。我们发现mit-n兼容性程度与RIAILs的寿命相关，但与觅食行为无关。几个已知的与衰老相关的QTL单独来看与线粒体类型没有关系，但总体上有一个与mit-n兼容性作用一致的微弱趋势。通过关联图谱分析，我们鉴定出293个与寿命连锁且与线粒体类型相关的单核苷酸多态性（SNP），这与mit-n兼容性的作用一致。我们进一步发现mit-n兼容性与线粒体的几个功能特征以及参与呼吸氧化途径的基因表达之间存在关联。这些结果提供了首个证据，表明mit-n兼容性在复杂性状的数量特征中发挥作用，并且可能为关于杂种的某些进化谜题提供信息。
