2012- 21st Annual NC State Undergraduate Research Symposium

Session Time : 4/10/12 10:30 AM - 4/10/12 11:45 AM

Content Area : Plant Biology

Poster Appointment: , -

Student Presenters :
Michael Fredrick Schwartz Plant Biology/Biology

Mentors and/or Co-Authors :
Bob Franks Genetics

Abstract Title : SEU and BUM1 affect shoot apical meristem termination and vegetative to floral transition in Arabidopsis thaliana

Abstract :
The shoot apical meristem (SAM) is a set of pluripotent cells that gives rise to above ground organs including leaves and flowers. The SAM normally progresses through different developmental phases; first a vegetative phase during which rosette leaves are produced and subsequently a reproductive phase. We are interested in two genes, SEUSS (SEU) and BUMBERSHOOT1 (BUM1), that are required for the maintenance of SAM growth and for the timely transition to the reproductive phase. seu single mutants have deformed flowers, a slight delay in the transition to flowering, and reduced plant height. While seu single mutants do not alter SAM development dramatically, mutations in the SEUSS paralogue, SEUSSLIKE2 (SLK2) show an enhancement of seu by the near complete loss of SAM formation in the seu slk2 double mutants. This suggests that the SEU family of proteins plays a critical role in SAM formation. bum1 mutants have defects in SAM maintenance, produce aerial rosettes, and display a reduced ability to complete the vegetative-floral transition. To examine the genetic relationship between seu and bum1 we generated seu bum1 double mutants. Examination of seu bum1 seedlings indicates that seu mutants dramatically enhance the phenotype of the bum1 mutants, with respect to premature SAM termination, and delayed transition to the reproductive phase. In order to further characterize these double mutants we will use rosette leaf counts to estimate the timing of the floral transition and will examine and compare floral organ tissue morphology between genotypes. Our results suggest a model in which SEU and BUM encode partially overlapping redundant activities that are important for proper SAM development.