Poster abstracts
Poster number 31 submitted by Katelyn Amstutz
Determining the role of a plant LINC complex in stomatal closure
Katelyn Amstutz (MCDB), Norman R. Groves (Department of Molecular Genetics, The Ohio State University), Iris Meier (Department of Molecular Genetics, The Ohio State University)
Abstract:
As climate change worsens, droughts across the globe have increased in frequency and severity. Understanding how plants regulate and resist drought stress will allow us to better create crops resilient to the changing climate. In response to drought, plants use the hormone Abscisic Acid to signal to pores called stomata, which are formed from two guard cells surrounding a central pore, to close. Loss of the Arabidopsis Klarsicht/ANC-1/Syne Homology (KASH) proteins AtSINE1 or AtSINE2 inhibits ABA-induced stomatal closure due to a decrease in calcium fluctuations and defects in actin reorganization. KASH proteins in the outer nuclear membrane (ONM) of Linker of Nucleoskeleton and Cytoskeleton (LINC) complexes interact with inner nuclear membrane SUN proteins. KASH proteins have a cytoplasmic region which interacts with the cytoskeleton, while SUN proteins can interact with the nuclear lamina. However, whether these interactions are important for SINE1 or SINE2 function during stomatal closure is unknown. In addition, the role of SUN proteins and the nuclear lamina in stomatal closure has not been determined.
Here, we have asked whether (a) nuclear envelope association, (b) membrane association, and (c) interaction with F-actin are involved in SINE1 and SINE2 function in stomatal closure. Mutant proteins with respective domain deletions have been tagged with GFP and placed under native promoters into sine1-1 and sine2-1 mutants. Subcellular localization has been confirmed and the plants are tested for rescue of ABA-induced stomatal closure. We further examined whether SUN and nuclear lamina components are required for stomatal closure by examining ABA-induced stomatal closure in a sun double mutant, sun1-KO sun2-KD, and two nuclear lamina mutants, crwn1 and crwn4.
Keywords: LINC complex, Stomata, Nucleus