LEFKOTHEA Regulates Nuclear and Chloroplast mRNA Splicing in Plants

First author: Gerasimos Daras; Affiliations: Agricultural University of Athens (雅典农业大学): Athens, Greece

Corresponding author: Polydefkis Hatzopoulos

Eukaryotic organisms accomplish the removal of introns to produce mature mRNAs through splicing. Nuclear and organelle splicing mechanisms are distinctively executed by spliceosome and group II intron complex, respectively. Here, we show that LEFKOTHEA, a nuclear encoded RNA-binding protein, participates in chloroplast group II intron and nuclear pre-mRNA splicing. Transiently optimized LEFKOTHEA nuclear activity is fundamental for plant growth, whereas the loss of function abruptly arrests embryogenesis. Nucleocytoplasmic partitioning and chloroplast allocation are efficiently balanced via functional motifs in LEFKOTHEA polypeptide. In the context of nuclear-chloroplast coevolution, our results provide a strong paradigm of the convergence of RNA maturation mechanisms in the nucleus and chloroplasts to coordinately regulate gene expression and effectively control plant growth.

真核生物中，成熟mRNA的产生需要通过剪切去除初级mRNA上的内含子序列。核和细胞器基因的剪切机制是不一样的，前者通过剪切体完成，而后者则通过II型内含子复合物完成。本文中，作者的研究显示一个由核编码的RNA结合蛋白LEFKOTHEA参与了叶绿体II型内含子和核mRNA前体的剪切。瞬间最优化LEFKOTHEA的核活力是保证植物正常生长的基础，而LEFKOTHEA蛋白的功能缺失则会导致植物胚胎发育异常。通过LEFKOTHEA多肽上的功能基序，植物能够有效保证核质分配和叶绿体分配之间的平衡。至于核与叶绿体的协同演化，本文的研究提供了一个核与叶绿体有关RNA成熟机制的趋同案例，该系统能够协同调控基因的表达，有效控制植物的正常生长。

通讯：Polydefkis Hatzopoulos

个人简介：1979年，希腊塞萨洛尼基亚里士多德大学，学士；1984年，纽约大学，博士。

doi: https://doi.org/10.1016/j.devcel.2019.07.024

Journal: Developmental Cell

Published date: August 22, 2019