Molecular characterization of pepper germin-like protein as the novel PR-16 family of pathogenesis-related proteins isolated during the resistance response to viral and bacterial infection

Abstract

To understand the molecular defense mechanism controlling the hypersensitive response (HR) better, we examined the hot pepper plant (Capsicum annuum L. cv. Bugang), which exhibits an HR in response to infection by Tobacco mosaic virus pathotype P0 (TMV-P0). A full-length cDNA clone was isolated by differential screening of a cDNA library that was constructed with mRNA extracted from hot pepper leaves during the resistance response to TMV-P0. The predicted amino acid sequence of the cDNA clone exhibited a high sequence similarity to germin-like protein (GLP). The CaGLP1 (Capsicum annuum GLP1) cDNA contains a single open reading frame of 660 bp encoding 220 amino acid residues. Upon inoculation with TMV or Xanthomonas, CaGLP1 transcripts were specifically accumulated in the incompatible interaction but not in the compatible interaction. In plants treated with salicylic acid (SA) or ethephon, which are signal molecules in the defense-related signal transduction pathway, CaGLP1 transcripts were accumulated rapidly. As far as we know, this is the first report that plant GLPs can be specifically induced during a defense response against viral infection. These data suggest that in the hot pepper plant CaGLP1 may be involved in the defense response to viral pathogens, and thus be classified as a new family of PR proteins, 'PR-16'.

Versatility of germin-like proteins in their sequences, expressions, and functions

“…oryzae) pathogen attack at early (6 h) and late (120 h) stages of infection, and it was found that along with other genes, a GLP (AK060864) gene was downregulated in the resistant cultivar over the susceptible one (Kottapalli et al 2007). The first report regarding the involvement of GLP to virus infection was given by Park et al 2004 …”

A hot pepper gene encoding WRKY transcription factor is induced during hypersensitive response to Tobacco mosaic virus and Xanthomonas campestris

“…Southern and northern blot hybridizations were carried out with 32 P-labeled probes. Blots were hybridized as described previously (Park et al 2001a(Park et al , 2002(Park et al , 2004a(Park et al , 2004b CaWRKY-a::smGFP construction and transient expression PCR was performed using the gene-specific oligonucleotide primers 5¢-GGGATCCTATGATCTCTTCTTC ATCA-3¢ and 5¢-CGGATCCCAGTTAAGGAAAGAG zCT-3¢. Subsequently, the termination codon of the CaWRKY-a cDNA was removed.…”

Estudio de la interacción entre naranjo amargo y el virus de la tristeza de los cítricos

“…En nuestros análisis también se observó que genes que codifican para proteínas multifuncionales tipo germinas, incluidas en la categoría funcional de pared celular, estaban sobre-expresados. Estas proteínas participan en la remodelación de la pared celular, pero a la vez pueden actuar directamente contra los patógenos y tener un papel protector (Park et al, 2004). Distintos estudios han demostrado la activación de estas proteínas como respuesta a la infección por virus (Park et al, 2004;Cristofani-Yali et al, 2007;Gandía et al, 2007;Irian et al, 2007;Elivira et al, 2008;Gasca-González, et al, 2008) Por último, distintas categorías relacionadas con la respuesta a estrés estaban también inducidas.…”

“…Estas proteínas participan en la remodelación de la pared celular, pero a la vez pueden actuar directamente contra los patógenos y tener un papel protector (Park et al, 2004). Distintos estudios han demostrado la activación de estas proteínas como respuesta a la infección por virus (Park et al, 2004;Cristofani-Yali et al, 2007;Gandía et al, 2007;Irian et al, 2007;Elivira et al, 2008;Gasca-González, et al, 2008) Por último, distintas categorías relacionadas con la respuesta a estrés estaban también inducidas. La inducción de genes relacionados con el estrés biótico y abiótico es un denominador común de las infecciones virales (Dardick et al, 2007;Babu et al, 2008).…”