Gel-based proteomic study for differential expression of Hevea brasiliensis root proteins in response to infection by soil fungus Rigidoporus microporus
It has been shown that Rigidoporous microporus infects Hevea brasiliensis root causing immature death of the plant NDASH a physiological symptom known as White Root Disease (WRD). This problem was studied in this work focusing on the identification of root proteins that were differentially expressed due to WRD employing 2-dimensional gel electrophoresis technique. Differential expression was observed for rubber plants (clone RRIM 2002) when infected with two pathogenic strains of R. microporus, namely AM and 2000, isolated from two different plantation areas in Malaysia: Melaka and Johor, respectively. Statistical analysis was done by Decodon using large sample set comprised of three biological replicates for every treatment condition. Proteins from differentially expressed gel spots were identified by ESI-Nano-LC-MS/MS (Orbitrap) system based on predicted protein database obtained from transcriptome analysis of the RNA samples taken from the same root samples. Differential protein expression indicated a mixed response of the plants to the pathogen. An induction of stress response was noticed from the upregulation of proteins involved in lignifications of cell wall. On the other hand, plants weak defence was obvious from the downregulation of some proteins involved in repair, defence and primary metabolism. Some examples are heat shock proteins, glycolytic proteins, latex allergen, etc. When it comes to the aggressiveness of the pathogen, relatively higher number of proteins were found to be differentially expressed in AM infected samples compared to the other strain. Some of the identified proteins with high fold change might be selected as candidate biomarkers for WRD after satisfactory validation.
Siddiqui, N., Middleton, C., Ribeiro, C., Atan, S. and Di Cola, A. 2017. Gel-based proteomic study for differential expression of Hevea brasiliensis root proteins in response to infection by soil fungus Rigidoporus microporus. Acta Hort. (ISHS) 1152:229-234
Hevea brasiliensis, white root disease, 2-dimensional gel-electrophoresis