A novel pepper membrane-located receptor-like protein gene CaMRP1 is required for disease susceptibility, methyl jasmonate insensitivity and salt tolerance.
Plant receptor proteins are involved in the signaling networks required for defense against pathogens. The novel pepper pathogen-induced gene CaMRP1 was isolated from pepper leaves infected with Xanthomonas campestris pv. vesicatoria (Xcv). This gene is predicted to encode a membrane-located receptor-like protein that has an N-terminal signal peptide and a C-terminal transmembrane helix. A CaMRP1-GFP fusion protein localized primarily to the plasma membrane of plant cells. Strong and early induction of CaMRP1 expression occurred following exposure of pepper plants to Xcv, Colletotricum coccodes, methyl jasmonate (MeJA) and wounding stress. Virus-induced gene silencing (VIGS) of CaMRP1 in pepper conferred enhanced basal resistance to Xcv infection, accompanied by induction of genes encoding basic PR1 (CaBPR1), defensin (CaDEF1) and SAR8.2 (CaSAR82A). In contrast, CaMRP1 overexpression (OX) in transgenic Arabidopsis plants resulted in increased disease susceptibility to Hyaloperonospora parasitica infection. Arabidopsis plants overexpressing CaMRP1 exhibited insensitivity to MeJA by causing reduced expression of MeJA-responsive genes. Overexpression also resulted in tolerance to NaCl and during salt stress, the expression of several abscisic acid-responsive genes was induced. Together, these results suggest that pepper CaMRP1 may belong to a new subfamily of membrane-located receptor-like proteins that regulate disease susceptibility, MeJA-insensitivity and salt tolerance.
An
Soo Hyun
SH
Laboratory of Molecular Plant Pathology, School of Life Sciences and Biotechnology, Korea University, Anam-dong, Sungbuk-ku, Seoul 136-713, Republic of Korea.
Choi
Hyong Woo
HW
Hwang
In Sun
IS
Hong
Jeum Kyu
JK
Hwang
Byung Kook
BK
D000085:Acetates / Q000737:chemistry*; D000595:Amino Acid Sequence; D002212:Capsicum / Q000235:genetics*; D002462:Cell Membrane / Q000378:metabolism; D003517:Cyclopentanes / Q000737:chemistry*; D018076:DNA, Complementary; D017343:Genes, Plant; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D054883:Oxylipins / Q000737:chemistry*; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology / Q000821:virology; D012333:RNA, Messenger / Q000235:genetics; D012965:Sodium Chloride / Q000737:chemistry*; D016959:Xanthomonas campestris / Q000302:isolation & purification / Q000472:pathogenicity
D000085:Acetates; D003517:Cyclopentanes; D018076:DNA, Complementary; D054883:Oxylipins; D012333:RNA, Messenger; D012965:Sodium Chloride; C072239:methyl jasmonate