华南农业大学赵杰堂团队的最新研究探明了LcMADS28和LcMADS27通过直接激活LcINVERTASE INHIBITOR1，协调调节荔枝种子早期发育。这一研究成果发表在2026年6月3日出版的国际学术期刊《遗传学报》上。

该课题组人员发现MADS-box转录因子LcMADS28是LcINH1的直接激活因子。LcMADS28在开花后15天的败育品种“糯米溪”的花珠和胚胎中表达量高，而在大种子品种“黑叶”中的表达量则低得多。进一步分析表明，LcMADS28与LcMADS27相互作用形成异源二聚体，直接结合LcINH1启动子并激活其转录。在‘Nuomici’中沉默LcMADS28可降低LcINH1表达，增加CWIN活性，促进胚和种子发育，降低果实脱落。

RNA-seq分析表明，与生长素和蔗糖代谢相关的基因在LcMADS28沉默后被激活。此外，LcMADS28在番茄和拟南芥中过表达会增加种子的败育。总之，他们的研究结果表明，LcMADS28和LcMADS27协同激活LcINH1来调节荔枝的早期种子发育，并提供了一个将MADS-box转录因子与转化酶/INH模块连接起来的机制框架。

据悉，种子败育是影响果实品质和产量的重要农艺性状。细胞壁转化酶（Cell wall invertase， CWIN）将蔗糖水解为葡萄糖和果糖，这两种物质既是营养物质，也是调节种子发育的信号分子，其活性受到转化酶抑制剂（INH）的抑制。然而，控制INH表达的转录调控因子仍然未知。

附：英文原文

Title: LcMADS28 and LcMADS27 coordinately regulate early seed development in Litchi chinensis through direct activation of LcINVERTASE INHIBITOR1

Author: anonymous

Issue&Volume: 2026/06/03

Abstract: Seed abortion is a critical agronomic trait affecting both fruit quality and yield. Cell wall invertase (CWIN) hydrolyzes sucrose into glucose and fructose, which serve as both nutrients and signaling molecules to regulate seed development, with its activity suppressed by invertase inhibitor (INH). However, the transcriptional regulators controlling INH expression remain unknown. Here, we identify the MADS-box transcription factor LcMADS28 as a direct activator of LcINH1. LcMADS28 is highly expressed in the funicle and embryo of the abortive-seeded cultivar ‘Nuomici’ at 15 days after anthesis (DAA), whereas its expression is much lower in the big-seeded cultivar ‘Heiye’. Further analysis reveals that LcMADS28 interacts with LcMADS27 to form a heterodimer that directly binds to the LcINH1 promoter and activates its transcription. Silencing LcMADS28 in ‘Nuomici’ reduces LcINH1 expression, which increases CWIN activity, promotes embryo and seed development, and lowers fruit abscission. RNA-seq analysis indicates that genes associated with auxin and sucrose metabolism are activated after LcMADS28 silencing. In addition, heterologous overexpression of LcMADS28 in tomato and Arabidopsis increases seed abortion. Together, our results indicate that LcMADS28 and LcMADS27 coordinately activate LcINH1 to regulate early seed development in lychee and provide a mechanistic framework linking MADS-box transcription factors with the invertase/INH module.

DOI: 10.1016/j.jgg.2026.05.013

Source: https://www.sciencedirect.com/science/article/abs/pii/S1673852726001876