Title: | Integration of ethylene and jasmonic acid signaling pathways in the expression of maize defense protein Mir1-CP |
Author(s): | Ankala A; Luthe DS; Williams WP; Wilkinson JR; |
Address: | "Department of Biochemistry and Molecular Biology, Mississippi State University, Mississipi State, MS 39762, USA" |
Journal Title: | Mol Plant Microbe Interact |
ISSN/ISBN: | 0894-0282 (Print) 0894-0282 (Linking) |
Abstract: | "In plants, ethylene and jasmonate control the defense responses to multiple stressors, including insect predation. Among the defense proteins known to be regulated by ethylene is maize insect resistance 1-cysteine protease (Mir1-CP). This protein is constitutively expressed in the insect-resistant maize (Zea mays) genotype Mp708; however, its abundance significantly increases during fall armyworm (Spodoptera frugiperda) herbivory. Within 1 h of herbivory by fall armyworm, Mir1-CP accumulates at the feeding site and continues to increase in abundance until 24 h without any increase in its transcript (mir1) levels. To resolve this discrepancy and elucidate the role of ethylene and jasmonate in the signaling of Mir1-CP expression, the effects of phytohormone biosynthesis and perception inhibitors on Mir1-CP expression were tested. Immunoblot analysis of Mir1-CP accumulation and quantitative reverse-transcriptase polymerase chain reaction examination of mir1 levels in these treated plants demonstrate that Mir1-CP accumulation is regulated by both transcript abundance and protein expression levels. The results also suggest that jasmonate functions upstream of ethylene in the Mir1-CP expression pathway, allowing for both low-level constitutive expression and a two-stage defensive response, an immediate response involving Mir1-CP accumulation and a delayed response inducing mir1 transcript expression" |
Keywords: | "Acetates/pharmacology Cyclopentanes/*metabolism/pharmacology Ethylenes/*metabolism/pharmacology Gene Expression Regulation, Plant/*physiology Oxylipins/*metabolism/pharmacology Plant Growth Regulators/pharmacology Plant Proteins/genetics/*metabolism Signa;" |
Notes: | "MedlineAnkala, A Luthe, D S Williams, W P Wilkinson, J R eng Research Support, U.S. Gov't, Non-P.H.S. 2009/11/06 Mol Plant Microbe Interact. 2009 Dec; 22(12):1555-64. doi: 10.1094/MPMI-22-12-1555" |