裸子植物线粒体基因组的进化研究

植物线粒体基因组因其大小变化大、结构变异复杂、与叶绿体及核基因组之间基因转移频繁等特征而备受关注，但以往对陆生植物线粒体基因组的进化研究主要涉及被子植物和苔藓植物，在裸子植物中仅研究了台东苏铁一个物种。因而，植物线粒体基因组进化式样和规律的探讨需要更加关注其它非开花植物。裸子植物是被子植物的姐妹群，且其线粒体基因组的遗传方式存在差异，是研究植物线粒体基因组进化的好材料。本项目拟对裸子植物不同支系代表性物种的线粒体基因组进行测序并作比较分析,通过对其大小、结构、组成和变异式样等的研究，揭示裸子植物线粒体基因组的进化模式；结合公共数据库中其它物种的线粒体基因组信息，探讨陆生植物线粒体基因组大小变化的规律及可能机制；同时，对裸子植物线粒体基因进行分子进化和系统发育分析，并结合线粒体基因组/基因的结构变异等信息，探讨裸子植物各大支系间的进化关系，尤其是倪藤类的系统位置。

The evolution of plant mitochondrial genomes has been given great attention due to their large and highly variable sizes, complex structures, and frequent incorporation of chloroplast and nuclear genes by intracellular and horizontal gene transfer. However, previous studies mainly focused on the mitochondrial genomes of angiosperms and bryophytes. To reveal the variation patterns and the evolutionary mechanisms of land plant mitochondrial genomes, more studies need to be conducted on non-flowering plants. Gymnosperms, as the sister group of angiosperms, are of special interest due to the different inheritance pathways of their mitochondrial genomes. In this project, we aim to investigate the evolution of mitochondrial genomes from the main lineages of gymnosperms by sequencing the mitochondrial genome and analyzing the genome structure and content, the distribution of protein-coding genes, introns and RNA editing sites, and the content of sequence repeats and foreign sequences. Combined with the available other plant mitochondrial genome sequences from public databases, we try to explore the size variation pattern of the land plant mitochondrial genome and its possible underlying mechanisms. Moreover, we will investigate the evolutionary relationships of the main lineages of gymnosperms using mitochondrial genes and phylogenetic information from the structural variation in the mitochondrial genome.