Transcriptional analysis for the difference in carotenoids accumulation in flesh and peel of white-fleshed loquat fruit

PLoS One. 2020 Jun 26;15(6):e0233631. doi: 10.1371/journal.pone.0233631. eCollection 2020.

Abstract

Loquat (Eriobotrya japonica Lindl.) is divided into yellow- and white-fleshed based on the difference in fruit color, and the variations in carotenoids accumulation are considered as the main reasons for this difference. Using RNA-seq technology, a transcriptome analysis was carried out on the flesh and peel of 'Baiyu' fruit during four different fruit development stages. A total of 172.53 Gb clean reads with an average of 6.33 Gb reads were detected for each library, and the percentage of Q30 was higher than 90.84%. We identified 16 carotenogenic and 13 plastid-lipid-associated protein (PAP) genes through RNA-seq. Of these, five carotenogenic and four PAP related genes exhibited remarkable differences in the expression patterns. Carotenoids biosynthetic genes, including DXS, PSY1 and VDE displayed higher expression levels in peel than that in the flesh. However, carotenoids decomposition gene, such as NCDE1, exhibited higher expression in flesh than that in the peel. Notably, all differentially expressed PAP genes showed higher expression levels in peel than flesh. We inferred that the differential accumulation of carotenoids in flesh and peel of 'Baiyu' is caused by the up- or down-regulation of the carotenogenic and PAP related genes. The functional analysis of these important genes will provide valuable information about underlying molecular mechanism of carotenoids accumulation in loquat.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biosynthetic Pathways / genetics
  • Carotenoids / metabolism*
  • Down-Regulation
  • Eriobotrya / genetics*
  • Eriobotrya / metabolism
  • Fruit / growth & development
  • Fruit / metabolism*
  • Gene Expression Regulation, Developmental*
  • Gene Expression Regulation, Plant*
  • Genes, Plant
  • RNA-Seq
  • Up-Regulation

Substances

  • Carotenoids

Grants and funding

This study was supported by Key Area Research and Development Program of Guangdong Province (2018B020202011). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.