Understanding the Functions of Plant Disease Resistance Proteins

Abstract

Many disease resistance (R) proteins of plants detect the presence of disease-causing bacteria, viruses, or fungi by recognizing specific pathogen effector molecules that are produced during the infection process. Effectors are often pathogen proteins that probably evolved to subvert various host processes for promotion of the pathogen life cycle. Five classes of effector-specific R proteins are known, and their sequences suggest roles in both effector recognition and signal transduction. Although some R proteins may act as primary receptors of pathogen effector proteins, most appear to play indirect roles in this process. The functions of various R proteins require phosphorylation, protein degradation, or specific localization within the host cell. Some signaling components are shared by many R gene pathways whereas others appear to be pathway specific. New technologies arising from the genomics and proteomics revolution will greatly expand our ability to investigate the role of R proteins in plant disease resistance.

Genetic mapping and transcription analyses of resistance gene loci in potato using NBS profiling

“…This simple yet sophisticated immune system involves an allele-speciWc genetic interaction between the products of host R genes and pathogen avirulence (Avr) genes (Flor 1971;Keen 1990). IdentiWcation of numerous functional R genes from model and crop species has revealed that the majority of these genes encode cytoplasmic proteins with nucleotide binding site (NBS) and leucine rich repeat (LRR) domains and that they often belong to complex loci comprised of arrays of related genes (reviewed in Martin et al 2003). Based on the genome sequences of Arabidopsis and rice (TAGI 2000;GoV et al 2002;Meyers et al 2002) the majority of plant genomes are estimated to contain hundreds of NBS-LRR genes.…”

Synthesis, Characterization, and Anti-Phytopathogen Evaluation of 6-Oxychitosan Derivatives Containing N-Quaternized Moieties in Its Backbone

“…Then, the mixture was cooled in the plate and a 5.0 mm diameter of fungi mycelia was transferred to the test plate and incubated at 28°C until the fungi mycelia of the blank control group reached the edge. Finally, the antifungal index was calculated according to (1).…”

“…They could cause at least 10% of global food losses. Meanwhile, they would give rise to human hunger and malnutrition [1]. More than 800 million people worldwide do not have enough food and 130 million people live for less than 1 dollar a day [2].…”

Proteomic Analysis of Stored Core Oil Palm Trunk (COPT) Sap Identifying Proteins Related to Stress, Disease Resistance and Differential Gene/Protein Expression

“…Also, these proteins were reportedly involved in the defence response of plants towards the infection of bacteria, insects, viruses or fungi (Martin et al 2003). Therefore, this suggests that upon storage, the COPT may also become infected by other microorganisms which trigger the disease-related protein to be upregulated.…”