Growth and Vegetative Development
Wauchope, Akelia , Abdelkader, Manar , Kapitonov, Vladimir , Miller, Stephen .
Analysis of transposon mobility and identification of additional gls genes in Volvox carteri.
Volvox carteri is a multicellular green alga that is comprised of only two distinct cell types: ~16 large cells called gonidia, and ~ 2000 small somatic cells that are specialized for reproduction and motility, respectively. V. carteri exhibits the simplest type of complete division of labor and thus lends itself to analysis of mechanisms that regulate cellular differentiation. During embryogenesis, beginning at the 6th of 11 cleavage stages, a series of asymmetric divisions in the anterior half of the embryo leads to the production of the larger gonidial initials. Mutational analysis has identified at least two gls (gonidialess) genes required for these asymmetric divisions. So far only one gls gene, glsA, has been cloned, after it was tagged by the class II (cut-and-paste) transposon Jordan. Class II transposons are especially useful for cloning Volvox genes because they often cause highly revertible mutations that can be used to determine linkage between the transposable element and the mutant phenotype. As such, Jordan has been used to tag and clone two other key developmental genes in Volvox, regA and invA. However, some previously isolated Gls mutants that are highly revertible (and thus very likely to contain class II transposon insertions at gls genes) do not appear to contain novel Jordan insertions. We are therefore using a bioinformatics approach to identify additional class II elements within the Volvox genome, with the goal of using one or more of them to clone other gls genes. We hope that insights gained from our studies of gls genes and asymmetric division in V. carteri will ultimately promote a greater understanding of how asymmetric division and cell-fate differentiation are regulated in other organisms.
Log in to add this item to your schedule
1 - University of Maryland - Baltimore County, Biology, 1000 Hilltop Circle, Biological Sciences Room480, Baltimore, Maryland, 21250, USA
2 - University of Maryland - Baltimore County, Biology
3 - Genetic Information Research Institute
4 - University of Maryland - Baltimore County, Biology
asymmetric cell division
Presentation Type: Plant Biology Abstract
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM