Plant & Animal Genomes XVI Conference

January 12-16, 2008
Town & Country Convention Center
San Diego, CA

Type Ii MADS-Box Genes Associated With Poplar Apical Bud Development And Dormancy

Kuang-Yu Chen , Gary, D. Coleman

  Plant Science and Landscape Architecture, 2102 Plant Science Building, University of Maryland, College Park, MD, 20742, USA

MADS-box genes encode a group of transcription factors that regulate the development of vegetative and reproductive organs in plants. The role of MADS-box genes in tree vegetative development, including bud development is not well understood. To advance the understanding of MADS-box genes in tree vegetative bud development and dormancy, 55 putative type II MADS-box genes representing 14 functional classes were identified from the JGI Populus trichocarpa genome database. DNA sequencing of cDNAs of the Poplar type II MADS-box genes revealed that a significant number of these genes possess different intron-exon structures than those predicted in the JGI Poplar genome database. Furthermore, splicing variants were detected for about 20% of the type II MADS-box genes. Using RT-PCR analysis, transcripts of all 14 classes were detected in either vegetative (shoot apex, leaf, bark, xylem, and root) or floral tissues. Functional studies of a Poplar FLC-like MADS-box (PtFLC2) gene using transgenic Poplar and Arabidopsis indicate a regulatory role for this gene in bud development. Moreover, these functional studies also suggest that splicing variants of PtFLC2 may be involved in regulating bud development. These results reveal the complexity of MADS-box gene expression in Poplar vegetative tissues and suggest that these genes may have important roles in vegetative developmental processes.