Cucumber abscisic acid 8′-hydroxylase Csyf2 regulates yellow flesh by modulating carotenoid biosynthesis

Xueting Wang, Boyan Jin, Wenjing Yan, Jiaxi Wang, Jun Xu, Congxi Cai, Xiaohua Qi, Qiang Xu, Xiaodong Yang, Xuewen Xu, Xuehao Chen

Research output: Contribution to journalArticlepeer-review

2 Scopus citations


Cucumber (Cucumis sativus L.) flesh is typically colorless or pale green. Flesh with yellow or orange pigment, determined mainly by carotenoid content and composition, is mostly found in semi-wild Xishuangbanna cucumber, which has a very narrow genetic background. Here, we identified a spontaneous cucumber mutant with yellow flesh (yf-343), which accumulated more β-cryptoxanthin and less lutein than regular cultivated European glasshouse-type cucumbers. Genetic analysis revealed that the yellow flesh phenotype was controlled by a single recessive gene. Through fine mapping and gene sequencing, we identified the candidate gene C. sativus yellow flesh 2 (Csyf2), encoding an abscisic acid (ABA) 8′-hydroxylase. Overexpression and RNAi-silencing of Csyf2 in cucumber hairy roots produced lower and higher ABA contents than in non-transgenic controls, respectively. Further, RNA-seq analysis suggested that genes related to ABA signal transduction were differentially expressed in fruit flesh between yf-343 and its wild type, BY, with white flesh. The carotenoid biosynthesis pathway was specifically enriched in fruit flesh at 30 days after pollination when yf-343 fruit flesh turns yellow. Our findings highlight a promising target for gene editing to increase carotenoid content, expanding our genetic resources for pigmented cucumber flesh breeding for improving the nutritional quality of cucumber.

Original languageEnglish (US)
Pages (from-to)1001-1015
Number of pages15
JournalPlant physiology
Issue number2
StatePublished - Oct 2023

All Science Journal Classification (ASJC) codes

  • Physiology
  • Genetics
  • Plant Science

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