Poster: Temperature responses

Abs # 122: Monitoring gene expression profiles during chilling acclimation in maize using cDNA microarrays

Presenter:	Gaddameedhi, Shobhan , Shobhan.Gaddameedhi@ndsu.nodak.edu
Authors	Gaddameedhi, Shobhan  (A)   Anderson, Marc D (A)
Affiliations:	(A): North Dakota State University

Chilling temperature (such as 4^oC) is known to cause damage to maize during seed germination and early seedling growth. Mesocotyl tissue appears to be the most sensitive to chilling in dark-grown seedlings. However, if seedlings are hardened by exposure to a milder low temperature (14^oC), they can become acclimated, exhibiting an enhanced tolerance to chilling. We are investigating changes in gene expression that occur during acclimation in an effort to better understand how maize seedlings protect themselves from chilling stress. We are monitoring the transcript profile in dark-grown mesocotyl tissues collected at different time points during a three-day acclimation treatment relative to that from unacclimated controls. Microarray analysis revealed hundreds of genes from diverse metabolic pathways that were responsive to acclimation, including representative genes that function in cell cycle regulation, protein degradation, transport and signal transduction. We are currently seeking common expression patterns among acclimation responsive genes in order to identify those that are potentially regulated by common factors. We anticipate that these data will provide a more complete picture of the coordination of genes important in the response to cold stress and will allow us to develop strategies to permanently improve chilling tolerance in maize seedlings.