Chongqing Key Laboratory of Economic Plant Biotechnology, Collaborative Innovation Center of Special Plant Industry in Chongqing, Chongqing Engineering Research Center for Special Plant Seedling, Institute of Special Plants, Chongqing University of Arts and Sciences, 402160, Yongchuan, China.
Key Laboratory of Horticulture Science for Southern Mountains Regions of Ministry of Education, College of Horticulture and Landscape Architecture, Southwest University, 400715, Chongqing, Beibei, China.
BMC Genomics. 2024 Mar 25;25(1):308. doi: 10.1186/s12864-024-10229-x.
Flowering at the right time is a very important factor affecting the stable annual yield of longan. However, a lack of knowledge of the regulatory mechanism and key genes of longan flowering restricts healthy development of the longan industry. Therefore, identifying relevant genes and analysing their regulatory mechanism are essential for scientific research and longan industry development.
DlLFY (Dimocarpus longan LEAFY) contains a 1167 bp open reading frame and encodes 388 amino acids. The amino acid sequence has a typical LFY/FLO family domain. DlLFY was expressed in all tissues tested, except for the leaf, pericarp, and pulp, with the highest expression occurring in flower buds. Expression of DlLFY was significantly upregulated at the early flower induction stage in "SX" ("Shixia"). The results of subcellular localization and transactivation analysis showed that DlLFY is a typical transcription factor acting as a transcriptional activator. Moreover, overexpression of DlLFY in Arabidopsis promoted early flowering and restrained growth, resulting in reduced plant height and rosette leaf number and area in transgenic plants. DNA affinity purification sequencing (DAP-Seq) analysis showed that 13 flower-related genes corresponding to five homologous genes of Arabidopsis may have binding sites and be putative target genes. Among these five flower-related genes, only AtTFL1 (terminal flower 1) was strongly inhibited in transgenic lines.
Taken together, these results indicate that DlLFY plays a pivotal role in controlling longan flowering, possibly by interacting with TFL1.
适时开花是龙眼稳定年产的一个重要因素。然而，龙眼开花调控机制和关键基因的知识缺乏限制了龙眼产业的健康发展。因此，鉴定相关基因并分析其调控机制对于科学研究和龙眼产业的发展是至关重要的。
DlLFY（Dimocarpus longan LEAFY）含有一个 1167 bp 的开放阅读框，编码 388 个氨基酸。该氨基酸序列具有典型的 LFY/FLO 家族结构域。DlLFY 在所有测试的组织中均有表达，除了叶片、果皮和果肉，而在花芽中表达量最高。在“SX”（“Shixia”）中，DlLFY 在早期花诱导阶段的表达显著上调。亚细胞定位和转录激活分析的结果表明，DlLFY 是一种典型的转录因子，作为转录激活因子发挥作用。此外，在拟南芥中过表达 DlLFY 促进了早期开花并抑制了生长，导致转基因植物的株高和莲座叶数量和面积减少。DNA 亲和纯化测序（DAP-Seq）分析表明，有 13 个与拟南芥的五个同源基因相对应的花相关基因可能具有结合位点，是潜在的靶基因。在这五个花相关基因中，只有 AtTFL1（终端花 1）在转基因系中受到强烈抑制。
综上所述，这些结果表明 DlLFY 在控制龙眼开花中起着关键作用，可能通过与 TFL1 相互作用来实现。
