College of Grassland Science and Technology, Sichuan Agricultural University, Chengdu 611130, China.
Genes (Basel). 2022 May 18;13(5):900. doi: 10.3390/genes13050900.
is the most widely cultivated perennial legume forage in temperate region around the world. It has rich nutritional value and good palatability, seasonal complementarity with grasses, and can improve the feed intake and digestibility of livestock. However, flowering time and inflorescence development directly affects the quality and yield of , as well as seed production. The ( gene family is a plant specific transcription factor family, which has been proved to play a critical role in regulating plant formation time and development of flowers. In this study, a total of 37 genes were identified from the whole genome of and were divided into nine clades based on phylogenetic tree. Seventeen genes have potential target sites for miR156. The conserved motif of squamosa promoter binding protein (SBP) contains two zinc finger structures and one NLS structure. Gene structure analysis showed that all genes contained SBP domain, while ankyrin repeat region was just distributed in part of genes. 37 genes were relatively dispersedly distributed on 16 chromosomes, and 5 pairs of segmental repeat genes were found, which indicated that segmental duplication was the main way of gene expansion. Furthermore, the gene expression profiling showed that , and were highly expressed only in the early stage of inflorescence development, while and are highly expressed only in the mature inflorescence. Significantly, the expression of and increased gradually with the development of inflorescences. The results of this study will provide valuable clues for candidate gene selection and elucidating the molecular mechanism of flowering regulation.
是世界温带地区栽培最广泛的多年生豆科牧草。它具有丰富的营养价值和良好的口感，与草具有季节性互补性，可以提高牲畜的饲料摄入量和消化率。然而，开花时间和花序发育直接影响的品质和产量，以及种子生产。（基因家族是一个植物特异性转录因子家族，已被证明在调节植物形成时间和花发育方面起着关键作用。在这项研究中，从的全基因组中鉴定出了 37 个基因，并根据系统发育树分为九个分支。17 个基因具有 miR156 的潜在靶位点。Squamosapromoterbindingprotein（SBP）的保守基序包含两个锌指结构和一个核定位信号结构。基因结构分析表明，所有基因都含有 SBP 结构域，而锚蛋白重复区仅分布在部分基因中。37 个基因相对分散地分布在 16 条染色体上，发现了 5 对片段重复基因，表明片段重复是基因扩展的主要方式。此外，基因表达谱表明，、和仅在花序发育的早期高度表达，而和仅在成熟的花序中高度表达。值得注意的是，和的表达随着花序的发育逐渐增加。本研究的结果将为候选基因选择和阐明开花调控的分子机制提供有价值的线索。
