Edinburgh, Scotland, United Kingdom - TAIR

Regulation of floral stem cells L04
Wednesday 11:00 - 11:30
Development
An Arabidopsis flower consists of a fixed number of floral organs derived from
stem cells in a floral meristem. Unlike stem cells in the shoot apical meristem,
which maintain their stem cell identity throughout plant development, those in
the floral meristem are terminated upon the production of the final floral organs,
the carpels. The floral homeotic transcription factor AGAMOUS (AG) not only
specifies the identities of the reproductive organs but also terminates the floral
stem cells by repression of the expression of WUS, a gene that promotes stem
cell identity. The regulation of WUS by AG, however, is unlikely to be direct. We
are striving to understand how AG terminates floral stem cells. We isolated an
ag allele, ag-10, which is completely functional in organ identity specification but
is occasionally defective in floral determinacy. We performed a genetic enhancer
screen in the ag-10 background and isolated mutations in several
complementation groups that enhance the floral determinacy defect. Cloning
and analysis of these genes have implicated small RNA- and chromatin-based
regulation of floral stem cell termination.
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Lijuan Ji
Xigang Liu
YunJu Kim
Xuemei Chen
Botany & Plant Sciences
University of California
Riverside
CA 92521
USA