Opaque-2 Regulates a Complex Gene Network Associated with Cell Differentiation and Storage Functions of Maize Endosperm. Issue 10 (27th September 2018)

• Record Type: Journal Article
• Authors: Zhan, Junpeng; Li, Guosheng; Ryu, Choong-Hwan; Ma, Chuang; Zhang, Shanshan; Lloyd, Alan; Hunter, Brenda G.; Larkins, Brian A.; Drews, Gary N.; Wang, Xiangfeng; Yadegari, Ramin
• Is Part Of: The Plant Cell. Volume 30:Issue 10(2018)
• Page Start: 2425
• Page End: 2446
• Publication Date: 2018-09-27
• DOI: 10.1105/tpc.18.00392
• Languages: English
• ISSNs: 1040-4651

Abstract

Abstract : Genome-wide analysis of genes regulated by the maize transcription factor Opaque-2 uncovered its functions in regulation of cell differentiation and endosperm storage development. Abstract: Development of the cereal endosperm involves cell differentiation processes that enable nutrient uptake from the maternal plant, accumulation of storage products, and their utilization during germination. However, little is known about the regulatory mechanisms that link cell differentiation processes with those controlling storage product synthesis and deposition, including the activation of zein genes by the maize ( Zea mays ) bZIP transcription factor Opaque-2 (O2). Here, we mapped in vivo binding sites of O2 in B73 endosperm and compared the results with genes differentially expressed in B73 and B73 o2 . We identified 186 putative direct O2 targets and 1677 indirect targets, encoding a broad set of gene functionalities. Examination of the temporal expression patterns of O2 targets revealed at least two distinct modes of O2-mediated gene activation. Two O2-activated genes, bZIP17 and NAKED ENDOSPERM2 ( NKD2 ), encode transcription factors, which can in turn coactivate other O2 network genes with O2. NKD2 (with its paralog NKD1) was previously shown to be involved in regulation of aleurone development. Collectively, our results provide insights into the complexity of the O2-regulated network and its role in regulation of endosperm cell differentiation and function.