Unraveling the KNOTTED1 regulatory network in maize meristems

Nathalie Bolduc; Alper Yilmaz; Maria Katherine Mejia-Guerra; Kengo Morohashi; Devin O'Connor; Erich Grotewold; Sarah Hake

doi:10.1101/gad.193433.112

Unraveling the KNOTTED1 regulatory network in maize meristems

¹Plant Gene Expression Center, U.S. Department of Agriculture-Agricultural Research Service, Plant and Microbial Biology Department, University of California at Berkeley, Berkeley, California 94720, USA;
²Department of Molecular Genetics, Center for Applied Plant Sciences, The Ohio State University, Columbus, Ohio 43210, USA

↵3 Present address: Department of Bioengineering, Yildiz Technical University, Istanbul 34210, Turkey.

Abstract

KNOTTED1 (KN1)-like homeobox (KNOX) transcription factors function in plant meristems, self-renewing structures consisting of stem cells and their immediate daughters. We defined the KN1 cistrome in maize inflorescences and found that KN1 binds to several thousand loci, including 643 genes that are modulated in one or multiple tissues. These KN1 direct targets are strongly enriched for transcription factors (including other homeobox genes) and genes participating in hormonal pathways, most significantly auxin, demonstrating that KN1 plays a key role in orchestrating the upper levels of a hierarchical gene regulatory network that impacts plant meristem identity and function.