| Abstract Detail
Growth and Vegetative Development Horvath, David [1], Anderson, James V. [2], Fennell, Anne [3], Taylor, Mark [4], Chao, Wun [5]. Microarray analysis and comparative genomics identifies conserved regulatory genes involved in flowering and seasonal bud dormancy. We have used our new 23,000 unigene Euphorbiaceae chip to study changes in gene expression associated with seasonal shifts in bud dormancy of the perennial weed leafy spurge (Euphorbia esula). Leafy spurge forms adventitious vegetative buds on its roots and crown. Once formed, these buds enter a state of paradormancy until fall when they become cold hardy and endodormant. Extended cold temperatures break endodormancy and make the buds flowering competent. Extreme cold keeps the buds ecodormant until spring when they initiate new shoot growth. In this study, underground adventitious buds were collected monthly (August through December) from plants grown outdoors over 5 consecutive years in Fargo ND. Microarray analysis identified ~1,000 genes that were differentially regulated during shifts from paradormancy through ecodormancy. Differentially-regulated genes involved in auxin responses, jasmonic acid responses, growth, cold stress, cellular transport, and meristem development (including BLIND) were identified. Comparisons among dormancy transcriptomes of leafy spurge, grape, and raspberry identified several genes involved in flowering responses with conserved dormancy-regulated expression patterns. Specifically, putative orthologues of EARLY FLOWERING 4 and a MADS-Box transcription factor related to SHORT VEGETATIVE PHASE were identified. These findings support our hypothesis that regulatory pathways controlling flowering and dormancy are linked, and are consistent with recent studies in poplar and peach that have linked dormancy and flowering regulatory mechanisms. Experiments to determine the function of these genes in dormancy responses are under way. Log in to add this item to your schedule
1 - USDA-ARS-RRVARC- Biosciences Research Lab, Plant Science, 1605 Albrecht Blvd., Fargo, ND, 58105, USA 2 - USDA-ARS-RRVARC- Biosciences Research Lab, Plant Science 3 - South Dakota State University, Dept. of Horticulture, Forestry, Landscape & Parks 4 - The Scottish Crop Research Institute, Plant Science 5 - USDA-ARS-RRVARC- Bioscience Research Lab, Plant Science
Keywords: dormancy vegetative buds comparative functional genomics.
Presentation Type: Plant Biology Abstract Session: P Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton Date: Sunday, July 8th, 2007 Time: 8:00 AM Number: P26009 Abstract ID:230 |