A MADS-box protein GhAGL8 promotes early flowering and increases yield without compromising fiber quality in cotton

• 全文链接

MADS-box蛋白GhAGL8促进棉花早花，在不影响纤维品质的前提下提高产量

关键词：

来源：

INDUSTRIAL CROPS AND PRODUCTS

全文链接：

//agri.nais.net.cn/topic/downloadFile/54aa8299-f43b-4834-99f2-cf64ff5590eb

来源地址：

https://www.sciencedirect.com/science/article/pii/S0926669025000913?via%3Dihub

资源所属：

棉花遗传育种

类型：

学术文献

语种：

英语

原文发布日期：

2025-02-01

摘要：

Flower bud formation is a critical stage of transition from vegetative to reproductive growth, which affects time of flowering and maturing in cotton (Gossypium hirsutum L.). However, the regulatory mechanisms of this process are poorly understood in cotton. To identify the genes involved in the regulation of flower bud formation, this study compared transcriptomes of an early-maturing cotton Zhongmian 619 and a late-maturing cotton 'Texas Marker-1'. An AGAMOUS-LIKE 8 (GhAGL8) gene is highly expressed in the stem apex meristem at the early stage of flower bud of Zhongmian 619 plants. Additionally, GhAGL8 consistently had higher expression levels in several tested early-maturing cultivars compared with late-maturing cultivars at the seedling stage. To assess the role of GhAGL8 in bud formation, the GhAGL8-deficient ghagl8 mutant and GhAGL8-overexpressing (GhAGL8OE) transgenic plants were generated. The ghagl8 plants flowered later while GhAGL8-OE plants flowered earlier than the wild-type plants. Overexpressing GhAGL8_D03 in Arabidopsis thaliana (L). also induced early bolting and flowering. Further investigation revealed that GhAGL8 binds to the CArG-box motifs in the promoter of TERMINAL FLOWER 1 (GhTFL1) gene, a key negative regulatory factor in the flowering pathway, and represses transcription of GhTFL1. GhAGL8 is also synchronously expressed with CAULIFLOWER (GhCAL), an AGAMOUS family gene, during flower bud formation and the resulting two proteins form a heterodimer. Overexpressing GhAGL8 also increases cotton yield without affecting fiber quality. Thus, the formation of a heterodimer from GhAGL8 and GhCAL promotes transition from vegetative to reproductive growth by repressing the expression of GhTFL1 in cotton. These findings provide molecular targets and candidate genes for breeding early maturing and high yield cotton cultivars.