%0 Journal Article %T Arabidopsis Heterotrimeric G-Proteins Play a Critical Role in Host and Nonhost Resistance against Pseudomonas syringae Pathogens %A Seonghee Lee %A Clemencia M. Rojas %A Yasuhiro Ishiga %A Sona Pandey %A Kirankumar S. Mysore %J PLOS ONE %D 2013 %I Public Library of Science (PLoS) %R 10.1371/journal.pone.0082445 %X Heterotrimeric G-proteins have been proposed to be involved in many aspects of plant disease resistance but their precise role in mediating nonhost disease resistance is not well understood. We evaluated the roles of specific subunits of heterotrimeric G-proteins using knock-out mutants of Arabidopsis G¦Á, G¦Â and G¦Ã subunits in response to host and nonhost Pseudomonas pathogens. Plants lacking functional G¦Á, G¦Â and G¦Ã1G¦Ã2 proteins displayed enhanced bacterial growth and disease susceptibility in response to host and nonhost pathogens. Mutations of single G¦Ã subunits G¦Ã1, G¦Ã2 and G¦Ã3 did not alter bacterial disease resistance. Some specificity of subunit usage was observed when comparing host pathogen versus nonhost pathogen. Overexpression of both G¦Á and G¦Â led to reduced bacterial multiplication of nonhost pathogen P. syringae pv. tabaci whereas overexpression of G¦Â, but not of G¦Á, resulted in reduced bacterial growth of host pathogen P. syringae pv. maculicola, compared to wild-type Col-0. Moreover, the regulation of stomatal aperture by bacterial pathogens was altered in G¦Á and G¦Â mutants but not in any of the single or double G¦Ã mutants. Taken together, these data substantiate the critical role of heterotrimeric G-proteins in plant innate immunity and stomatal modulation in response to P. syringae. %U http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0082445