Poster: Root Biology

Abs # 524: Microarray analyses of maize root meristems: insights into meristem development and function

Presenter:	Feldman, Lewis , feldman@nature.berkeley.edu
Authors	Feldman, Lewis  (A)   Jiang, Keni  (A)   Zhang, Shibo  (A)   Zhu, Tong  (B)   Chang, Sherman  (B)
Affiliations:	(A): University of California, Berkeley (B): Torrey Mesa Research Institute

We investigated the controls for development and function in the maize root apex which is comprised of three distinct populations of cells: the root cap, the quiescent center and the proximal meristem. Using microarray analyses we discovered unique transcriptional activities in each of these 3 populations. The root cap expresses the largest number of unique transcripts, many of which are associated with carbohydrate (sugar) metabolism; a lesser number of highly expressed transcripts are associated with transport and signal transduction. The proximal meristem uniquely expresses a number of putative transcription factors, and also transcripts for lateral root production and lignin biosynthesis. The quiescent center expresses transcripts associated with auxin transport or auxin responses. Unique up- and down-regulated transcription factors are also noted. Because the quiescent cells divide rarely, we focused on transcripts associated with regulation of the cell cycle. A significant number of unique quiescent center transcripts are related to redox status. We discuss how the microarray data provide insight into the development and function of root meristems.