Roles of auxin pathways driving maize root growth

Auxin signaling is a key regulator of root morphogenesis in angiosperms, yet this pathway is understudied in maize and little is known regarding genetic factors that determine maize root architecture. Recent reports have demonstrated that root architecture can directly impact yield and drought resistance in maize. The overall objective of this project is to understand the key regulatory events governing auxin-mediated root development in maize using an integrated molecular genomics-to-phenotype approach. Specifically, we will (1) define roles for ZmARF27 in early root development (2) uncover functions of ZmPILS2 and ZmPILS6 (also called ZmPINY and ZmPIN14) in promoting maize root morphogenesis and (3) determine predictive multi-scale auxin responsive regulatory networks that underpin maize root architecture. The characterization of three novel root mutants will fill current knowledge gaps regarding how auxin response factors and efflux carriers control root development in maize and test the hypothesis that altered root architecture impacts yield in maize. In addition, these studies will provide genome-wide quantification for the levels of transcripts, proteins, and protein phosphorylation in primary and seminal maize roots following auxin treatment by RNA-sequencing and peptide mass spectrometry. These large-scale data will be used to build co-expression and predictive gene regulatory networks that can be used to tailor maize root architecture for optimal yield. Altogether these studies fit with the NIFA strategic goal to “advance our Nation’s ability to achieve global food security and fight hunger” (NIFA Strategic Plan FY2014-2018). This project was recently funded through the Physiology of Agricultural Plants program at USDA NIFA AFRI and fits their plant growth and developmental processes program area priority.

A chart about the roots of a plant.

Funding Organization: USDA AFRI NIFA

Duration: 12/21/2020 to 05/31/2023

Award Amount: $450,000.00

Award Number: IOW05613

Principal Investigator(s): Dr. Dior Kelley (PD), Dr. Justin Walley (Co-PD)