Chinese Bulletin of Botany ›› 2023, Vol. 58 ›› Issue (1): 34-50.DOI: 10.11983/CBB22171

Special Issue: 杂粮生物学专辑 (2023年58卷1期)

• EXPERIMENTAL COMMUNICATIONS • Previous Articles     Next Articles

Analyses on the Transcription and Structure Variation of β-carotene Isomerase Gene Family in Foxtail Millet

Hui Zhang, Hongkai Liang, Hui Zhi, Linlin Zhang, Xianmin Diao*(), Guanqing Jia*()   

  1. Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China

Abstract: Plant architecture is of great importance for yield improvement of cereal crops, and improvement of plant architecture is of great significance for improving crop yield potential. As a newly identified plant hormone, strigolactones is one of plant hormones regulating branching and tillering by inhibiting the elongation of axillary buds. β-carotene isomerase is the key enzyme for strigolactone synthesis. By the typical domain Pfam:DUF4033, all members in the β-carotene isomerase gene family in foxtail millet (Setaria italica) were identified (Seita.8G168400, Seita.6G088800, Seita.3G- 050900), encoding 271 to 277 amino acid residues with molecular weight ranging from 30.1 kDa to 30.4 kDa, isoelectric point ranging from 5.85 to 9.31, and instability coefficient ranging from 38.48 to 74.47. All members were subcellularly localized in chloroplast, and were grouped into three different evolutionary branches. Cis-element analysis revealed that SiD27-1 (Seita.8G168400) was involved in regulating circadian rhythm, auxin-mediated development, and response to drought and low temperature. Transcription of SiD27-1 was down-regulated in foxtail millet accessions with more tillers, and in low phosphorus treatment could respond to faster than all other members. Haplotype variation analysis revealed that H001 of SiD27-1 may contribute more to plant height, heading date and grain yield than other haplotypes. We inferred that SiD27-1 was involved in strigolactone synthesis and plant architecture in foxtail millet. It laid the foundation for in-depth analysis of regulatory mechanism of D27s on the formation of foxtail millet tillering, and provided allelic variation sites for molecular breeding of foxtail millet.

Key words: β-carotene isomerase, gene families, transcription, haplotype variation, foxtail millet