Gene duplication at the Fascicled ear1 locus controls the fate of inflorescence meristem cells in maize

第一作者：Yanfang Du

第一单位：华中农业大学

通讯作者：Zuxin Zhang

 Abstract 

背景回顾：Plant meristems are self-renewing groups of pluripotent stem cells that produce lateral organs in a stereotypical pattern. 

研究对象：Of interest is how the radially symmetrical meristem produces laminar lateral organs. Both the male and female inflorescence meristems of the dominant Fascicled ear (Fas1) mutant fail to grow as a single point and instead show deep branching. 

主要研究：Positional cloning of two independent Fas1 alleles identified an ～160 kb region containing two floral genes, the MADS-box gene, zmm8, and the YABBY gene, drooping leaf2 (drl2). 

结果：Both genes are duplicated within the Fas1 locus and spatiotemporally misexpressed in the mutant inflorescence meristems. Increased zmm8 expression alone does not affect inflorescence development; however, combined misexpression of zmm8, drl2, and their syntenic paralogs zmm14 and drl1, perturbs meristem organization.

假设：We hypothesize that misexpression of the floral genes in the inflorescence and their potential interaction cause ectopic activation of a laminar program, thereby disrupting signaling necessary for maintenance of radially symmetrical inflorescence meristems.

验证假设：Consistent with this hypothesis, RNA sequencing and in situ analysis reveal altered expression patterns of genes that define distinct zones of the meristem and developing leaf. 

结论：Our findings highlight the importance of strict spatiotemporal patterns of expression for both zmm8 and drl2 and provide an example of phenotypes arising from tandem gene duplications.

 通讯作者 

**张祖新**

doi: https://doi.org/10.1073/pnas.2019218118

Journal: PNAS

Published date: Feb 16, 2021