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bioRxiv · 10.1101/2022.12.21.521534

Comparative analysis of chloroplast genome between wild and cultivated Rehmannia glutinosa Libosch.

Abstract

Rehmanniae radix, as a tonic Chinese medicine, has a good therapeutic effect on cardiovascular and cerebrovascular diseases and central nervous system diseases, and has a good development prospect in the international market. R.glutinosa Libosch has a large number of source varieties, and the wild and cultivated varieties are different types of R.glutinosa Libosch. There has been a lot of controversy in the formulation of scientific names for wild and cultivated types of R.glutinosa Libosch. In order to learn more about the genetic information of wild R.glutinosa Libosch and explore the phylogenetic relationship between wild R.glutinosa Libosch and cultivated R.glutinosa Libosch. In the current study, we constructed and annotated a complete circular chloroplast genome of wild R.glutinosa Libosch. The chloroplast genome of wild R.glutinosa Libosch. is 153,678 bp in length, including two inverted repeat (IR) regions of 25,759 bp, separated by a large single copy (LSC) region of 84,544 bp and a small single copy (SSC) region of 17,616 bp. The GC content of whole chloroplast genome is 37.9%. The genome contains 133 different genes, including 88 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Among them, 23 genes contained introns, 50 SSR loci and 49 long repeats were found by Microsatellite scan, and codon use showed obvious A, T base preference. Nine variation regions were screened by mVISTA analysis and combined with DnaSP analysis, and psaJ-rpl33 was finally identified as a region with high variation, which could be used as a candidate DNA barcode for later interspecific identification of R.glutinosa Libosch.. Neighbor-joining method phylogenomic analysis showed that wild R.glutinosa Libosch. formed a monophyletic group, and was sister to other groups of R.glutinosa Libosch.The results of this study revealed the chloroplast genome information of wild R.glutinosa Libosch in detail, and found the genetic information difference between wild and cultivated R.glutinosa Libosch. which laid the foundation for the variety identification, genetic engineering, biosynthesis and other studies.

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Yang, H., Yohei, S., Lian, C., Zhang, L., Wang, L., Yang, J., Xue, S., Chen, S.. 2022-12-22. Comparative analysis of chloroplast genome between wild and cultivated Rehmannia glutinosa Libosch.. https://doi.org/10.1101/2022.12.21.521534

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