Exploring the SiCCT Gene Family and Its Role in Heading Date in Foxtail Millet

Congcong Li; Jian Ma; Genping Wang; Haiquan Li; Hailong Wang; Guoliang Wang; Yanmiao Jiang; Yanan Liu; Guiming Liu; Guoqing Liu; Ruhong Cheng; Huan Wang; Jianhua Wei; Lei Yao

doi:10.3389/fpls.2022.863298

Exploring the SiCCT Gene Family and Its Role in Heading Date in Foxtail Millet

Front Plant Sci. 2022 Jun 9:13:863298. doi: 10.3389/fpls.2022.863298. eCollection 2022.

Authors

Congcong Li^{1

2

3}, Jian Ma^{1

4}, Genping Wang⁵, Haiquan Li⁵, Hailong Wang^{1

2}, Guoliang Wang^{1

2}, Yanmiao Jiang⁵, Yanan Liu⁵, Guiming Liu^{1

2}, Guoqing Liu⁵, Ruhong Cheng⁵, Huan Wang³, Jianhua Wei^{1

2}, Lei Yao^{1

2}

Affiliations

¹ Beijing Academy of Agriculture and Forestry Sciences, Beijing, China.
² Institute of Biotechnology Research, Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology, Beijing, China.
³ Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China.
⁴ Institute of Vegetable Research, Beijing Key Laboratory of Vegetable Germplasm Improvement, National Engineering Research Center for Vegetables, Beijing, China.
⁵ Institute of Millet Crops, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang, China.

Abstract

CCT transcription factors are involved in the regulation of photoperiod and abiotic stress in Arabidopsis and rice. It is not clear that how CCT gene family expand and regulate heading date in foxtail millet. In this study, we conducted a systematic analysis of the CCT gene family in foxtail millet. Thirty-nine CCT genes were identified and divided into four subfamilies based on functional motifs. Analysis showed that dispersed duplication played a predominant role in the expansion of CCT genes during evolution. Nucleotide diversity analysis suggested that genes in CONSTANS (COL)-like, CCT MOTIF FAMILY (CMF)-like, and pseudoresponse response regulator (PRR)-like subfamilies were subjected to selection. Fifteen CCT genes were colocalized with previous heading date quantitative trait loci (QTL) and genome-wide association analysis (GWAS) signals. Transgenic plants were then employed to confirm that overexpression of the CCT gene SiPRR37 delayed the heading date and increased plant height. Our study first investigated the characterization and expansion of the CCT family in foxtail millet and demonstrated the role of SiPRR37. These results lay a significant foundation for further research on the function of CCT genes and provide a cue for the regulation of heading date.

Keywords: CCT gene family; SiPRR37; foxtail millet; gene duplication; heading date; transcriptional factor.