| Abstract Detail
Cell Walls del Campillo, Elena [1], Korth, Jen [2], Asif, Mehar [2], Cole, Stephanie [2], Adgobe, Fadeke [2]. AtCel4 is an Endo β-1,4 glucanase with Roles in Secondary Cell Wall and Flower Development. The role of endo β-1,4 glucanase (cellulase) genes in Arabidopsis is still unknown. Some members of this family have been found in association with wall disassembly while KORRIGAN, a membrane-associated form, has been associated with cellulose biosynthesis. We analyzed an endo β-1,4 glucanase (cellulase) gene, AtCel4, whose immediate upstream neighbor is a sucrose synthase (At4g02280) positioned in divergent orientation. Since both genes appeared to be co-expressed in several tissues and sucrose synthase is hypothesized to be a component of the cellulose biosynthesis complex, we tested if AtCel4 could also play a role in cellulose accumulation. Transgenic plants expressing GUS driven by the AtCel4 promoter showed activity in cells of several aerial tissues near where phloem fibers are formed. ATCEL4-GUS was also detected in the shoot-root tissue undergoing secondary thickening in cells where secondary phloem is formed. In addition, GUS activity was also found in the carpel during early stages of flower development associated with the vascular strands of the replum, Thus, AtCel4 expression is specific to cells of primary phloem that forms fibers and to cells of the vascular cambium or the secondary phloem. We obtained a homozygote cel4 line from the SALK collection and confirmed it to be a true null by RT-PCR. The mutant showed no differences in root or hypocotyl growth compared to wild type. Mature plants showed a small increase in stem height, rosette size and cellulose content in stem, petioles and lamina compared to wild type and surprisingly, the mutant flowered significantly earlier when grown in short days and low temperature. In contrast with Korrigan, AtCel4 alone appears to have a negative impact on cellulose accumulation and its activity contributes to delay flowering.
Log in to add this item to your schedule
Related Links:
del Campillo lab site
1 - University of Maryland, Department of Cell Biology and Molecular Genetics, College Park, Maryland, 21037, USA
2 - University of Maryland, Department of Cell Biology and Molecular Genetics
Keywords:
cell wall
plant growth and development
endo beta 1,4 glucanases.
Presentation Type: Plant Biology Abstract
Session: P
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM
Number: P17013
Abstract ID:551 |
