Arabidopsis Heterotrimeric G-Proteins Play a Critical Role in Host and Nonhost Resistance againstPseudomonas syringae Pathogens

作者：Lee Seonghee; Rojas Clemencia M; Ishiga Yasuhiro; Pandey Sona; Mysore Kirankumar S^*

来源：PLos One, 2013, 8(12).

DOI：10.1371/journal.pone.0082445

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 alpha, G beta and G gamma subunits in response to host and nonhost Pseudomonas pathogens. Plants lacking functional G alpha, G beta and G gamma 1G gamma 2 proteins displayed enhanced bacterial growth and disease susceptibility in response to host and nonhost pathogens. Mutations of single G gamma subunits G gamma 1, G gamma 2 and G gamma 3 did not alter bacterial disease resistance. Some specificity of subunit usage was observed when comparing host pathogen versus nonhost pathogen. Overexpression of both G alpha and G beta led to reduced bacterial multiplication of nonhost pathogen P. syringae pv. tabaci whereas overexpression of G beta, but not of G alpha, 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 alpha and G beta mutants but not in any of the single or double G gamma 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.

• 出版日期2013-12-5