The parent-of-origin lncRNA MISSEN regulates rice endosperm development

背景回顾：The cereal endosperm is a major factor determining seed size and shape. 

提出问题：However, the molecular mechanisms of endosperm development are not fully understood.

研究对象：Long noncoding RNAs (lncRNAs) function in various biological processes. 

主要发现：Here we show a lncRNA, MISSEN, that plays an essential role in early endosperm development in rice (Oryza sativa).

结果1-MISSEN负调控胚乳发育：MISSEN is a parent-of-origin lncRNA expressed in endosperm, and negatively regulates endosperm development, leading to a prominent dent and bulge in the seed.

结果2-MISSEN-HeFP-细胞骨架-胚乳发育：Mechanistically, MISSEN functions through hijacking a helicase family protein (HeFP) to regulate tubulin function during endosperm nucleus division and endosperm cellularization, resulting in abnormal cytoskeletal polymerization. 

结果3：Finally, we revealed that the expression of MISSEN is inhibited by histone H3 lysine 27 trimethylation (H3K27me3) modification after pollination.

结论：Therefore, MISSEN is the first lncRNA identified as a regulator in endosperm development, highlighting the potential applications in rice breeding.

 摘 要 

谷类作物的胚乳是决定其种子大小和形状的主要因素。然而，胚乳发育的分子机制尚不完全清楚。长链非编码RNA（lncRNAs）在各种生物学过程中发挥作用。本文中，作者发现长链非编码RNA MISSEN在水稻早期胚乳发育中起着非常重要的作用。MISSEN是一个来源于亲本的lncRNA，在胚乳中表达，负调控胚乳的发育，导致种子出现明显的凹陷和凸起。在胚乳核分裂和胚乳细胞化过程中，MISSEN通过劫持一个解旋酶家族蛋白HeFP来调节的微管蛋白功能，导致异常的细胞骨架聚合。最后，作者发现在授粉后，组蛋白H3赖氨酸27三甲基化（H3K27me3）修饰会抑制MISSEN的表达。因此，MISSEN是第一个被鉴定为胚乳发育调节因子的lncRNA，其在水稻育种中存在潜在的应用价值。

 通讯作者 

** 陈月琴 **