Regulation and function of the pepper pectin methylesterase inhibitor (CaPMEI1) gene promoter in defense and ethylene and methyl jasmonate signaling in plants

Abstract

Analysis of the promoters of defense-related genes is valuable for determining stress signaling and transcriptional activation during pathogen infection. Here, we have isolated and functionally characterized the promoter region of the pepper (Capsicum annuum) pectin methylesterase inhibitor 1 (CaPMEI1) gene in transiently transformed tobacco plants and stably transformed Arabidopsis plants. Among four 5' deletion constructs analyzed, the -958-bp CaPMEI1 promoter induced a high level of GUS reporter activity in tobacco leaf tissue, driven by pathogen infection as well as by ethylene and methyl jasmonate (MeJA) treatment. The 204-bp region from -958 bp to -754 bp of the CaPMEI1 promoter is responsible for the stress-responsive expression. In addition, the pepper transcription factor CARAV1 activated the CaPMEI1 promoter in tobacco leaves, whereas the transcription factor CAbZIP1 did not. In the transgenic Arabidopsis plants, the -958 bp CaPMEI1 promoter was functionally regulated by developmental cues, bacterial and oomycete pathogen infections, and treatment with ethylene and MeJA. Histochemical GUS staining analyses of Arabidopsis tissues revealed that the CaPMEI1 promoter was mainly activated in leaf veins in response to various biotic and abiotic stimuli. Together, these results suggest that CaPMEI1 promoter activation may be a critical molecular event for host defense response and ethylene- and MeJA-mediated CaPMEI1 gene expression.

Are PECTIN ESTERASE INHIBITOR Genes Involved in Mediating Resistance to Rhynchosporium commune in Barley?

“…The PECTIN METHYL ESTERASE INHIBITOR gene CaPMEI1 from pepper ( Capsicum annuum L.) was isolated and functionally characterized [ 32 , 33 ]. Virus-induced gene silencing of CaPMEI1 in pepper conferred enhanced susceptibility to Xanthomonas campestris pv.…”

“…tomato , but not to the biotrophic pathogen Hyaloperonospora parasitica [ 32 ]. Furthermore, the promoter of CaPMEI1 induced a high level of GUS reporter activity in tobacco leaf tissue, driven by pathogen infection as well as by ethylene and methyl jasmonate treatment, suggesting an involvement in host defense response [ 33 ].…”

Characterization and Transcriptional Profiling of Ginkgo biloba Mevalonate Diphosphate Decarboxylase Gene (GbMVD) Promoter Towards Light and Exogenous Hormone Treatments

“…Each promoter-GUS fusion construct was introduced into A. tumefaciens EHA105 via electroporation. Agrobacterium-mediated transient expression assays were performed according to the An et al (2009). Agrobacterium-mediated transient expression was conducted on fully expanded tobacco leaves, and the intercellular spaces of the intact leaves were infiltrated with the bacterial suspension.…”

A transcriptomics approach uncovers novel roles for poly(ADP-ribosyl)ation in the basal defense response in Arabidopsis thaliana

“…Pectinesterases are known to be involved such physiological responses as pollen tube growth and abscission. A pectin methylesterase inhibitor protein was demonstrated to be necessary for basal disease resistance and antifungal activity in pepper [ 84 , 85 ], but this enzyme’s role in plant defenses remains unclear. In this current study, the absence of PARG1 led to downregulation of a pectin methylesterase inhibitor gene.…”