OPTIMIZATION OF PROTEIN ISOLATION AND PRELIMINARY COMPARATIVE PROTEOMICS OF PATHOGENIC FUSARIUM OXYSPORUM f. sp. CUBENSE (P-FOC) AND NON PATHOGENIC FUSARIUM OXYSPORUM (np-FO)

Abstract

Panama wilt of banana caused by F. oxysporum f. sp. cubense (Foc) is a devastating disease of banana and in severe condition causes 100% yield loss. In order to understand the molecular mechanism of pathogenicity for the effective management of the wilt disease, three protocols (MgCl2/CHAPS, TCA-Acetone and TCA/Phenol-SDS) were evaluated to extract protein from Foc mycelial tissue. Comparatively, TCA/Phenol-SDS method of protein precipitation and extraction resulted in maximum protein quantity (0.76±0.025 mg/g of mycelial tissue) and ca.600 spots were identified in CBB stained gels. A comparative proteomic study conducted between pathogenic F. oxysporum f. sp. cubense (P-Foc) (race 1, VCG 0124) and non-pathogenic Fusarium oxysporum (np-Fo) revealed a difference at the proteome level. In the comparative proteomics study, 23 spots were found to be differentially expressed with ≥ 1.5 fold intensity differences between P-Foc and np-Fo. Preliminarily, six spots (5 significantly upregulated and 1 unique proteins) from P-Foc was randomly picked and subjected to MALDITOF/MS analysis. Further, MASCOT search and functional annotation revealed that these up regulated proteins identified in P-Foc may be involved in invasive growth, signal transduction and pathogen persistence during adverse condition.