Poster abstracts

Poster number 20 submitted by Katelyn Amstutz

Determining the role of the LINC complex in stomatal closure

Katelyn Amstutz (Molecular, Cellular and Developmental Biology), Norman Groves (Department of Molecular Genetics, The Ohio State University), Iris Meier (Department of Molecular Genetics, The Ohio State University; Center for RNA Biology, 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. Plants balance water loss with gas exchange through the opening and closing of pores called stomata, formed from two guard cells surrounding the central pore. In response to drought, plants produce the hormone Abscisic Acid (ABA), which causes a signaling cascade of Ca2+ and reactive oxygen species, resulting in a loss of turgor pressure and a filamentous actin (F-actin) rearrangement. Recently, loss of the Arabidopsis Klarsicht/ANC-1/Syne Homology (KASH) proteins AtSINE1 or AtSINE2 was shown to result in a defect in ABA-induced stomatal closure. KASH proteins form the outer nuclear membrane (ONM) component of Linker of Nucleoskeleton and Cytoskeleton (LINC) complexes, where they interact with inner nuclear membrane (INM) 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.
To examine which connections of SINE1 and SINE2 are required for stomatal closure, domain deletions of the SINE1 and SINE2 domains implicated in these interactions have been tagged with GFP and placed under their native promoters into sine1-1 and sine2-1 mutants, respectively. Localizations of these domain deletions have been obtained, and these lines will be examined for rescue of ABA-induced stomatal closure. If the LINC complex is required for the role of SINEs in stomatal closure, SUN and lamina mutants will be examined for defects in ABA-induced stomatal closure.

Keywords: LINC complex, Plant Biology