Abstract
Pattern formation of leaf epidermis is regulated by intercellular signaling. Stomatal development is initiated when a protodermal cell division to form the meristemoid and its sister cell. Meristemoids are precursors of stomatal cells. A non-stomatal cell may be derived from a non-MMC protodermal cell, meristemoid, or meristemoid-sister cell. EPF2 negatively regulates formation of MMC, whereby limiting epidermal cell density. EPF1 regulates asymmetric cell division plane of MMC so that the meristemoid will not be formed in contact. Transcription factors SPEECHLESS(SPCH) and MUTE are known to be necessary for the formative asymmetric cell division and differentiation into stoma, respectively. We examined functional relationship between EPF2 and SPCH, and EPF1 and MUTE. Our results indicated that the SPCH is necessary for EPF2 expression but EPF2 does not affect SPCH expression, and that EPF1 regulates a step before MUTE is expressed.
