April 2, 2013

As I write this, I have dirt underneath my fingernails and I love it.  Spring is here, and I have begun playing in the dirt and cheering for my budding vegetable garden seedlings.  I love the food plants provide us, but they’re also fascinating models for understanding cell biology and developmental biology.  Today’s image is from a paper identifying a player in the development of stomata, which are important plant organs.

Stomata are pore organs on leaves that regulate gas and water vapor exchange in plants.  They are made of pairs of guard cells that regulate the size of the stomata openings to let air in and oxygen out.  A recent paper describes the identification of a protein that regulates the maturing and functioning of stomatal guard cells.  Negi and colleagues identified SCAP1, a transcription factor, that when mutated results in irregularly-shaped guard cells.  These mutants also lack the ability to control stomatal opening and closing.  SCAP1 regulates the transcription of known guard cell development genes.  The images above show a wild-type plant (top) with normal developing stomata at all stages (mature stomata is right-most image).  In a scap1 mutant (bottom), however, later stages of stomata development are defective and result in stomata with a floppy or irregular appearance.

Negi, J., Moriwaki, K., Konishi, M., Yokoyama, R., Nakano, T., Kusumi, K., Hashimoto-Sugimoto, M., Schroeder, J., Nishitani, K., Yanagisawa, S., & Iba, K. (2013). A Dof Transcription Factor, SCAP1, Is Essential for the Development of Functional Stomata in Arabidopsis Current Biology, 23 (6), 479-484 DOI: 10.1016/j.cub.2013.02.001
Copyright ©2013 Elsevier Ltd. All rights reserved.