Whole-transcriptome profiles of Chrysanthemum seticuspe improve genome annotation and shed new light on mRNA-miRNA-lncRNA networks in ray florets and disc florets

BMC Plant Biol. 2022 Nov 5;22(1):515. doi: 10.1186/s12870-022-03889-y.

Abstract

Background: Chrysanthemum seticuspe has emerged as a model plant species of cultivated chrysanthemums, especially for studies involving diploid and self-compatible pure lines (Gojo-0). Its genome was sequenced and assembled into chromosomes. However, the genome annotation of C. seticuspe still needs to be improved to elucidate the complex regulatory networks in this species.

Results: In addition to the 74,259 mRNAs annotated in the C. seticuspe genome, we identified 18,265 novel mRNAs, 51,425 novel lncRNAs, 501 novel miRNAs and 22,065 novel siRNAs. Two C-class genes and YABBY family genes were highly expressed in disc florets, while B-class genes were highly expressed in ray florets. A WGCNA was performed to identify the hub lncRNAs and mRNAs in ray floret- and disc floret-specific modules, and CDM19, BBX22, HTH, HSP70 and several lncRNAs were identified. ceRNA and lncNAT networks related to flower development were also constructed, and we found a latent functional lncNAT-mRNA combination, LXLOC_026470 and MIF2.

Conclusions: The annotations of mRNAs, lncRNAs and small RNAs in the C. seticuspe genome have been improved. The expression profiles of flower development-related genes, ceRNA networks and lncNAT networks were identified, laying a foundation for elucidating the regulatory mechanisms underlying disc floret and ray floret formation.

Keywords: Chrysanthemum seticuspe; Flower development; Genome annotation; ceRNA; lncNAT.

MeSH terms

  • Chrysanthemum* / genetics
  • Chrysanthemum* / metabolism
  • Gene Regulatory Networks
  • MicroRNAs* / genetics
  • MicroRNAs* / metabolism
  • RNA, Long Noncoding* / genetics
  • RNA, Long Noncoding* / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Transcriptome

Substances

  • RNA, Long Noncoding
  • MicroRNAs
  • RNA, Messenger