Genome-wide identification of flowering time genes associated with vernalization and the regulatory flowering networks in Chinese cabbage

• Published in: Plant biotechnology reports Vol. 12; no. 5; pp. 347 - 363
• Main Authors: Jung, Won Yong, Lee, Areum, Moon, Jae Sun, Kim, Youn-Sung, Cho, Hye Sun
• Format: Journal Article
• Language: English
• Published: Singapore Springer Singapore 01.10.2018; Springer Nature B.V; 한국식물생명공학회
• Subjects: Agriculture; Biomedical and Life Sciences; Biotechnology; Brassica oleracea; Cell Biology; Chinese cabbage; Crops; Divergence; Enhancers; Flowering; FLOWERING LOCUS T gene; Gene expression; Genes; Genomes; Inbreeding; Life Sciences; Original Article; Plant Biochemistry; Plant Sciences; Polymerase chain reaction; Regulatory mechanisms (biology); Repressors; Ribonucleic acid; RNA; Vernalization; 농학; Flowering pathway; Flowering time (Ft) gene; Vernalization; Chinese cabbage; RNA-Seq profiling
• ISSN: 1863-5466; 1863-5474
• DOI: 10.1007/s11816-018-0500-0

Flowering time (Ft) is the most important characteristic of Chinese cabbage with high leaf yields and late-flowering are favorable traits, while little knowledge on genes involved in Ft and the flowering mechanism in this crop. In this study, we conducted genome-wide RNA-seq analysis using an inbred Chinese cabbage ‘4004’ line in response to vernalization and compared the Ft gene expression with radish crop. A number of Ft genes which play roles in flowering pathways were performed quantitative RT-PCR analysis to verify the regulatory flowering gene network in Chinese cabbage. We found that a total of 223 Ft genes in Chinese cabbage, and 50 of these genes responded to vernalization. The majority of flowering enhancers were upregulated, whereas most flowering repressors were downregulated in response to vernalization as confirmed by RT-qPCR. Among the major Ft genes, the expression of BrCOL1-2, BrFT1 / 2, BrSOC1 / 2 / 3, BrFLC1 / 2 / 3 / 5 , and BrMAF was strongly affected by vernalization. In reference to comparative RNA-seq profiling of Ft genes, Chinese cabbage and radish revealed substantially different vernalization response in particular GA flowering pathway. Thus, this study provides new insight into functional divergence in flowering pathways and the regulatory mechanisms in Brassicaceae crops. Further analysis of the major integrator genes between early and late-flowering inbred lines facilitates understanding flowering trait variation and molecular basis of flowering in Chinese cabbage.