Plants can program and reprogram their genomes to create genetic variation and epigenetic modifications, leading to phenotypic plasticity. While consequences of genetic changes are well understood, the basis for transgenerational inheritance of epigenetic variation remains elusive. Shuai Cao, and Z. Jeffrey Chen review contributions of external (environmental) and internal (genomic) factors to initiation and establishment of epigenetic memory during plant evolution, crop domestication, and modern breeding. Understanding and harnessing epigenetic inheritance will help developing effective breeding and biotechnological strategies to improve crop yield and resilience. The cover image of a scientist pruning a hedge symbolizes the selection process during domestication aimed at “shaping” optimal plant traits. Image credit: Grayson Ticer.
PJ:南京农业大学发现调控拟南芥叶片大小的新机制
叶片大小是影响作物产量的一个关键因素。本研究发现DnaJ-like zinc finger domain-containing protein ORANGE (OR)在蛋白水平上与转录因子TCP7互作。TCP通过诱导 cell cycle gene CYCLIN D 1;1 (CYCD1;1)促进endoreduplication。但是过表达OR导致叶片变小，而沉默该基因则会导致叶片变大。
遗传分析显示，OR抑制了TCP对endoreduplication的促进作用。OR本身受到TCP的诱导，OR反过来通过抑制TCP对靶基因CYCD1;1的表达调控，从而形成了一种负反馈机制
小结：本研究揭示了OR通过抑制TCP转录因子功能来负调控叶片大小的机制。
Postulated working model for the regulation of endoreduplication and cell size by the OR–TCP7 interaction. In this model, TCP7 induces the expression of the cell cycle gene CYCD1;1, which positively regulates endoreduplication and cell size. TCP7 also induces the expression of OR, which represses the binding capability of TCP7 to the promoter region of CYCD1;1. Thus, the transcript abundance of CYCD1;1 and the endoreduplication level in leaf cells are fine-tuned by the OR–TCP7 homeostasis.
原文：ORANGE interplays with TCP7 to regulate endoreduplication and leaf size
