美国加州大学伯克利分校George Chuck等研究人员合作发现，一个调控发育边界和分生组织命运的网络在玉米驯化过程中发挥重要作用。2024年10月16日，《自然—遗传学》杂志在线发表了这项成果。

据研究人员介绍，在驯化过程中，早期农民选择了不同的营养和生殖性状，但由于基因的上位性和功能冗余，定位其致因位点一直具有挑战性。

通过结合染色质免疫沉淀测序和全基因组关联分析，研究人员发现了一个控制这两类性状的发育调节因子，并且该因子处于多个驯化位点的上游。tasselsheath4（tsh4）是一个新的玉米驯化基因，它通过建立发育边界并指定分生组织命运来发挥作用，尽管它并未在这些边界内表达。

TSH4通过一个双重负反馈环路实现这一功能，目标并抑制那些对其产生负调控作用的微小RNA。TSH4与一对同源基因具有冗余功能，积极调控一系列驯化位点，同时指定了现代玉米中使种子产量翻倍的分生组织。TSH4在产量提升中具有关键作用，并有助于生成理想的作物植株结构，这解释了为何它成为了驯化过程中的主要目标。

附：英文原文

Title: A regulatory network controlling developmental boundaries and meristem fates contributed to maize domestication

Author: Dong, Zhaobin, Hu, Gaoyuan, Chen, Qiuyue, Shemyakina, Elena A., Chau, Geeyun, Whipple, Clinton J., Fletcher, Jennifer C., Chuck, George

Issue&Volume: 2024-10-16

Abstract: During domestication, early farmers selected different vegetative and reproductive traits, but identifying the causative loci has been hampered by their epistasis and functional redundancy. Using chromatin immunoprecipitation sequencing combined with genome-wide association analysis, we uncovered a developmental regulator that controls both types of trait while acting upstream of multiple domestication loci. tasselsheath4 (tsh4) is a new maize domestication gene that establishes developmental boundaries and specifies meristem fates despite not being expressed within them. TSH4 accomplishes this by using a double-negative feedback loop that targets and represses the very same microRNAs that negatively regulate it. TSH4 functions redundantly with a pair of homologs to positively regulate a suite of domestication loci while specifying the meristem that doubled seed yield in modern maize. TSH4 has a critical role in yield gain and helped generate ideal crop plant architecture, thus explaining why it was a major domestication target.

DOI: 10.1038/s41588-024-01943-z

Source: https://www.nature.com/articles/s41588-024-01943-z