Adaptation of a parasitic lifestyle by Cuscuta gronovii Willd. ex Roem. & Schult.: large scale gene deletion, conserved gene orders, and low intraspecific divergence

Yang Ni; Mei Jiang; Haimei Chen; Linfang Huang; Pinghua Chen; Chang Liu

doi:10.1080/23802359.2021.1911702

Adaptation of a parasitic lifestyle by Cuscuta gronovii Willd. ex Roem. & Schult.: large scale gene deletion, conserved gene orders, and low intraspecific divergence

Mitochondrial DNA B Resour. 2021 Apr 20;6(4):1475-1482. doi: 10.1080/23802359.2021.1911702.

Authors

Yang Ni¹, Mei Jiang², Haimei Chen², Linfang Huang², Pinghua Chen¹, Chang Liu²

Affiliations

¹ Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, National Engineering Research Center of Sugarcane, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, P. R. China.
² Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine from Ministry of Education, Engineering Research Center of Chinese Medicine Resources from Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, P. R. China.

Abstract

Cuscuta gronovii Willd. ex Roem. & Schult. is a parasitic plant and widely distributed in Europe and North America. Here, we compared the plastome sequences of a C. gronovii plant collected from China and other 16 Cuscuta plastomes, including one C. gronovii plastome from North America. The plastome was 86,727 bp in size with a pair of inverted repeats (IRs) of 14,354 bp, a large single-copy (LSC) region of 50,956 bp, and a small single-copy (SSC) region of 7,063 bp. We predicted 97 genes in the plastome, including 61 protein-coding genes, eight ribosomal RNA genes, and 28 transfer RNA genes. We detected a total of 21 microsatellite, 16 tandem, and ten interspersed repeats in the genome. Gene contents analysis of 17 Cuscuta plastomes showed the loss of the entire ndh gene family. The phylogenomic analysis using 22 shared protein sequences shows that the two C. gronovii formed a cluster. Thirteen of Cuscuta plastomes showed no rearrangement. The other three showed smaller inversions and smaller numbers of gene deletion. Next, we identified the two INDELs, one SNP site between the two C. gronovii plastomes. And we identified two putative RNA editing sites. Lastly, to distinguish between C. gronovii and two medicinal Cuscuta species, C. chinensis and C. australis, we identified ten molecular markers based on the genome sequences. The overall large-scale gene loss, conserved gene order, low intraspecific divergence are consistent with the adaptation of C. gronovii to a parasitic lifestyle.

Keywords: Cuscuta gronovii; RNA editing site; SNP; analysis; markers.

Grants and funding

The National Mega-Project supported this work for Innovative Drugs of China [2019ZX09735-002], and National Science & Technology Fundamental Resources Investigation Program of China [2018FY100705], National Natural Science Foundation of China [81872966]. The funders were not involved in the study design, data collection and analysis, decision to publish, or manuscript preparation.