The complete plastid genome of Cotinus coggygria and phylogenetic analysis of the Anacardiaceae

Abstract Cotinus coggygria Scop. (Anacardiaceae) is an important ornamental tree with beautiful characteristics that is grown in China. In this study, the complete plastid genome of C. coggygria was sequenced and assembled. This genome was 158,843 bp in size and presented a typical tetrad structure, consisting of a large single-copy region (87,121 bp), a pair of inverted repeat regions (26,829 bp), and a small single-copy region (18,064 bp). A total of 134 genes were annotated, including 88 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. We observed a deletion that caused the loss of the rpl32 gene, and a small expansion of IR regions resulted in the trnH gene accessing IR regions; two copies were obtained. Phylogenetic analysis showed that C. coggygria was most closely related to Pistacia, with 100% bootstrap support within Anacardiaceae. In this study, we report the plastid genome of Cotinus species for the first time, which provides insight into the evolution of the plastid genome in Anacardiaceae and promotes the understanding of Cotinus plants.

摘要 黄栌（Cotinus coggygria Scop.，漆树科Anacardiaceae）是我国广泛栽培的重要观赏树种，兼具优异的观赏特性。本研究完成了黄栌完整质体基因组（plastid genome）的测序与组装工作。该基因组全长158843 bp，具有典型的四分体结构，包含大单拷贝区（large single-copy region，LSC，87121 bp）、一对反向重复区（inverted repeat region，IR，26829 bp）以及小单拷贝区（small single-copy region，SSC，18064 bp）。共注释得到134个功能基因，其中包括88个蛋白编码基因、38个转运RNA（transfer RNA，tRNA）基因以及8个核糖体RNA（ribosomal RNA，rRNA）基因。研究发现一处缺失突变导致rpl32基因丢失，同时反向重复区发生轻微扩张，使得trnH基因进入反向重复区并获得两个拷贝。系统发育分析结果显示，黄栌与黄连木属（Pistacia）植物亲缘关系最近，在漆树科内的自举支持率达100%。本研究首次报道了黄栌属（Cotinus）植物的质体基因组，该成果为阐明漆树科植物质体基因组的演化历程提供了新的研究视角，同时有助于加深对黄栌属植物的科学认知。