Poster: Temperature Responses

Abs # 200: Interplant communication via airborne methyl jasmonate confers cold tolerance in an Arabidopsis mutant

Presenter:	Zhu, Jian-Kang , jkzhu@ag.arizona.edu
Authors	Zhu, Jian-Kang  (A)   Song, Chun-peng  (A)   Jagendorf, Andre  (B)   Stevenson, Rebecca  (A)
Affiliations:	(A): Department of Plant Sciences, University of Arizona (B): Department of Plant Biology, Cornell University

Plants vary in their ability to withstand chilling temperatures. A previously described mutant, los1-1, which is a cold-sensitive allele of translational Elongation Factor 2 (EF2), is more sensitive to cold than is the wild type, and will die after a period of two weeks in the dark at 4 °C. The mutant could be rescued from the cold- and dark-induced death by light, by feeding sucrose, or by planting in close proximity to wild type seedlings. The latter, interesting fact, suggested a possible airborne signal coming from wild type plants; and indeed added methyl jasmonate (MeJA) or jasmonic acid (JA) also rescued the los1-1 seedlings. Further support for this concept came from a finding that wild type seedlings in the cold and dark release volatile MeJA, while los1-1 seedlings do not. Added MeJA was found to permit new protein synthesis and to restore cold-responsive gene expression in the los1-1 mutant. Even in the wild type LOS1 background, added jasmonate enhanced cold-responsive gene expression, while jasmonate deficiency reduced plant tolerance to cold and dark conditions. A speculative model is presented to explain the beneficial effect of MeJA on plant chilling tolerance.