The 30th International Conference on Arabidopsis Research (ICAR 2019)

491 / 2019-02-28 14:19:52

Identify regulators of asymmetric protein localization and measure cell polarity in the stomatal lineage

Polarity protein,Stomatal development,Quantitative measurement,Cell polarity,Ethylene

Plenary track > Cell Biology

Generating cell polarity prior to asymmetric cell division determines diverse daughter cell fates during development. In the Arabidopsis stomatal lineage, few proteins (e.g. BASL) are polarly localized at the cell cortex before division and contribute to the physical and fate asymmetries of the subsequent division. However, how these proteins achieve their striking polar localization is unknown. In a genetic screen, we identified a mutation in Constitutive Triple Response 1 (CTR1), a negative regulator of ethylene signaling pathway, along with several other mutants that resulted in depolarization of polarity proteins in stomatal lineage cells. In order to precisely measure polarity protein distribution along the cell periphery in those mutants in an unbiased fashion, we developed a semi-automatic imaging analysis tool, named POME. Coupled with downstream statistics analysis, POME can generate regression models and provide detailed characteristics of the protein localization pattern. With the accurate polarity measurement with POME, we tested core genetic components that contribute to ethylene’s regulation of stomatal development, as well as elements that may cross talk with this hormone. Currently, we are applying genetic, cell biology, and biochemical approaches to dissect the relationship between the stem cell polarity and the ethylene signaling pathway in the context of stomatal development.