Activation of plant plasma membrane Ca2+-permeable channels by race-specific fungal elicitors

Angela C Gelli, Verna J. Higgins, Eduardo Blumwald

Research output: Contribution to journalArticlepeer-review

150 Scopus citations


The response of plant cells to invading pathogens is regulated by fluctuations in cytosolic Ca2+ levels that are mediated by Ca2+-permeable channels located at the plasma membrane of the host cell. The mechanisms by which fungal elicitors can induce Ca2+ uptake by the host cell were examined by the application of conventional patch-clamp techniques. Whole-cell and single-channel experiments on tomato (Lycopersicon esculentum L.) protoplasts revealed a race-specific fungal elicitor-induced activation of a plasma membrane Ca2+-permeable channel. The presence of the fungal elicitor resulted in a greater probability of channel opening. Guanosine 5'-[β-thio]diphosphate, a GDP analog that locks heterotrimeric G-proteins into their inactivated state, abolished the channel activation induced by the fungal elicitor, whereas guanosine 5'[γ-thio]triphosphate, a nonhydrolyzable GTP analog that locks heterotrimeric G-proteins into their activated state, produced an effect similar to that observed with the fungal elicitor. Mastoparan, which stimulates GTPase activity, mimicked the effect of GTP[γ]S. The addition of HA1004 (a protein kinase inhibitor) in the presence of the elicitor totally abolished channel activity, whereas okadaic acid (a protein phosphatase inhibitor) moderately enhanced channel activity, suggesting that the activation of the channel by fungal elicitors is modulated by a heterotrimeric G-protein-dependent phosphorylation of the channel protein.

Original languageEnglish (US)
Pages (from-to)269-279
Number of pages11
JournalPlant Physiology
Issue number1
StatePublished - Jan 1997
Externally publishedYes

ASJC Scopus subject areas

  • Plant Science


Dive into the research topics of 'Activation of plant plasma membrane Ca2+-permeable channels by race-specific fungal elicitors'. Together they form a unique fingerprint.

Cite this