Involvement of specific calmodulin isoforms in salicylic acid-independent activation of plant disease resistance responses

被引：204

作者：

Heo, WD ^{[1
]}

Lee, SH ^{[1
]}

Kim, MC ^{[1
]}

Kim, JC ^{[1
]}

Chung, WS ^{[1
]}

Chun, HJ ^{[1
]}

Lee, KJ ^{[1
]}

Park, CY ^{[1
]}

Park, HC ^{[1
]}

Choi, JY ^{[1
]}

Cho, MJ ^{[1
]}

机构：

[1] Gyeongsang Natl Univ, Dept Biochem, Plant Mol Biol & Biotechnol Res Ctr, Chinju 660701, South Korea

来源：

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA | 1999年 / 96卷 / 02期

关键词：

D O I：

10.1073/pnas.96.2.766

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

The Ca2+ signal is essential for the activation of plant defense responses, but downstream components of the signaling pathway are still poorly defined. Here we demonstrate that specific calmodulin (CaM) isoforms are activated by infection or pathogen-derived elicitors and participate in Ca2+-mediated induction of plant disease resistance responses. Soybean CaM (SCaM)-4 and SCaM-5 genes, which encode for divergent CaM isoforms, were induced within 30 min by a fungal elicitor or pathogen, whereas other SCaM genes encoding highly conserved CaM isoforms did not show such response, This pathogen-triggered induction of these genes specifically depended on the increase of intracellular Ca2+ level. Constitutive expression of SCaM-4 and SCaM-5 in transgenic tobacco plants triggered spontaneous induction of lesions and induces an array of systemic acquired resistance (SAR)-associated genes. Surprisingly, these transgenic plants have normal levels of endogenous salicylic acid (SA), Furthermore, coexpression of nahG gene did not block the induction of SAR-associated genes in these transgenic plants, indicating that SA is not involved in the SAR gene induction mediated by SCaM-4 or SCaM-5. The transgenic plants exhibit enhanced resistance to a wide spectrum of virulent and avirulent pathogens, including bacteria, fungi, and virus. These results suggest that specific CaM isoforms are components of a SA-independent signal transduction chain leading to disease resistance.

引用

页码：766 / 771

页数：6

共 41 条

[1]

An G., 1988, PLANT MOL BIOL MANUA

[2] Syringolide 1 triggers Ca2+ influx, K+ efflux, and extracellular alkalization in soybean cells carrying the disease-resistance gene Rpg4 [J].