EAPSI: Investigating molecular connections between internal and external cues that affect seedling development

Favero David S, Pullman WA

Investigators

Abstract

A key question in regards to improving crop productivity is how plants integrate both external signals, such as light, and internal signals, such as cues from hormones, to alter growth and development. Previous work on the model plant Arabidopsis thaliana identified several DNA-binding proteins which play similar roles in suppressing seedling elongation in response to light. Additional evidence indicates that these proteins may also interact with internal plant hormone signaling pathways. Based on these two pieces of information, it seems likely that these genes serve as molecular integration points between external light signals and internal hormone pathways that influence seedling development. This hypothesis will be tested in collaboration with Dr. Keiko Sugimoto at the RIKEN Center for Sustainable Resource Science in Yokohama, Japan. RIKEN is renowned in the field of plant hormone research, and Dr. Sugimoto and other researchers at the institute possess specialized, cutting-edge technology and expertise which will allow two unique but complementary approaches to be used to investigate this question. The AT-HOOK MOTIF NUCLEAR LOCALIZED (AHL) gene family, specific to and yet ubiquitous in plants, modulates hypocotyl growth in light-grown Arabidopsis seedlings. This research will investigate if the AHLs serve as a genetic integration point between light signaling and phytohormone pathways in the control of hypocotyl growth, by using two different biochemical techniques. The first specific aim will test if AHLs bind directly to DNA sequences associated with plant hormone signaling pathways, using chromatin immunoprecipitation followed by sequencing (ChIP-SEQ). In specific aim two, mass spectrometry will be used to evaluate if AHL genes influence the endogenous levels of various plant hormones. Specifically, hormone profiles will be generated from the seedlings of various AHL mutants and compared. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science.