title: Arabidopsis GDSL lipase 2 plays a role in pathogen defense via negative regulation of auxin signaling.
abstract: GLIP1 was isolated previously from Arabidopsis, as a salicylic acid-responsive secreted GDSL lipase that functions in resistance to Alternaria brassicicola [I.S. Oh, A.R. Park, M.S. Bae, S.J. Kwon, Y.S. Kim, J.E. Lee, N.Y. Kang, S. Lee, H. Cheong, O.K. Park, Secretome analysis reveals an Arabidopsis lipase involved in defense against Alternaria brassicicola. Plant Cell 17 (2005) 2832-2847.]. To extend our knowledge of the roles played by GLIPs in Arabidopsis, we conducted functional studies of another family member, GLIP2. GLIP2 transcripts were expressed in young seedlings, as well as in the root and stem tissues of mature plants. GLIP2 transcript levels were elevated by treatment with salicylic acid, jasmonic acid and ethylene. Recombinant GLIP2 proteins possessed lipase and anti-microbial activities, inhibiting germination of fungal spores. In comparison to wild type plants, T-DNA insertion glip2 mutants exhibited enhanced auxin responses, including increased lateral root formation and elevated AUX/IAA gene expression. When challenged with the necrotropic bacteria Erwinia carotovora, glip2 mutants exhibited more susceptible phenotypes than wild type plants. These results suggest that GLIP2 plays a role in resistance to Erwinia carotovora via negative regulation of auxin signaling.
authors.affiliation: School of Life Sciences and Biotechnology, Korea University, Anam-dong, Seongbuk-gu, Seoul 136-701, Republic of Korea.
authors.forename: Dong Sook
authors.initials: DS
authors.lastname: Lee
authors.forename: Bo Kyung
authors.initials: BK
authors.lastname: Kim
authors.forename: Sun Jae
authors.initials: SJ
authors.lastname: Kwon
authors.forename: Hak Chul
authors.initials: HC
authors.lastname: Jin
authors.forename: Ohkmae K
authors.initials: OK
authors.lastname: Park
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000382:microbiology*; D043182:Carboxylesterase / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D015870:Gene Expression; D007210:Indoleacetic Acids / Q000378:metabolism* / Q000494:pharmacology; D016973:Pectobacterium carotovorum / Q000187:drug effects; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D007210:Indoleacetic Acids; D011994:Recombinant Proteins; D043182:Carboxylesterase