AUTHOR=Chen Jianhui , Ma Hongping , Fan Haili , Lin Fan , Chai Tuanyao , Wang Hong 

TITLE=De novo assembly and comparative analysis of the mitochondrial genome of Reynoutria japonica

JOURNAL=Frontiers in Genetics

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2023.1289811

DOI=10.3389/fgene.2023.1289811

ISSN=1664-8021

ABSTRACT=<p><italic>Reynoutria japonica</italic> Houtt. is an important medical plant with a long history of thousands of years in China, however, its mitochondrial genome (mitogenome) has not been reported yet. In this work, we reported and analyzed the <italic>R. japonica</italic> mitogenome. The main results include: The <italic>R. japonica</italic> mitogenome was 302,229 bp in length and encoded 48 genes, including 27 protein-coding genes (PCGs), 3 rRNA genes, and 18 tRNA genes. Repeat sequence analysis revealed that there were 54 repeat sequences ranging from 193 bp to 1,983 bp in the <italic>R. japonica</italic> mitogenome. Relative synonymous codon usage (RSCU) analysis showed that leucine (900, 11.01%) and serine (732, 8.96%) were the two most abundant amino acids, and the codons with RSCU values showed the preference of A or T ending when greater than 1. The RNA editing sites of PCGs in the <italic>R. japonica</italic> mitogenome were characterized, and 299 RNA editing sites were found. Extensive sequences transfer between mitochondrion and chloroplast were found in <italic>R. japonica</italic>, where 11 complete plastid-derived tRNA genes stayed intact in the <italic>R. japonica</italic> mitogenome. Three genes (<italic>ccmFC</italic>, <italic>cox1</italic>, and <italic>nad1</italic>) were seen to play essential roles in the evolution through selection pressure analysis. The phylogenetic analysis showed that <italic>Fallopia multiflora</italic> was the closest species with <italic>R. japonica</italic>, in consistency with the results of chloroplast genome. Overall, the current work presents the first mitogenome of <italic>R. japonica</italic> and could contribute to the phylogenetic analysis of the family Polygonaceae.</p>