Proteomic Analysis Reveals Differentially Accumulated Proteins in Banana Somaclonal Variants

Aims: To compare the protein profile of leaves from normal and giant banana plants to identify differentially accumulated proteins specific to each type.

Place and Duration of Study: Central Molecular Biology Lab (LCBM), between April and November of 2017.

Methodology: Protein samples were analyzed in triplicate by two-dimensional gel electrophoresis. The gels were stained with Coomassie Blue G250 and evaluated by the Image Master 2D Platinum 5.0 software. Differentially abundant proteins were treated with trypsin enzyme, and aliquots of each hydrolysate sample were analyzed by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometer. The molecular mass profile of each sample was subjected to comparative analysis using the MASCOT program and the NCBI database.

Results: Of the 36 differentially abundant proteins that were analyzed, 21 were identified as being related to root metabolism, photosynthesis, protein translation, and carbon and nitrogen fixation. Notably, glutamine synthetase was more abundant in the leaves of the giant banana plants.

Conclusion: This pioneering work used proteomic analysis to identify differentially abundant proteins in the leaves of normal and giant banana plants. Glutamine synthetase was revealed as a potential molecular marker that could be used to screen out plants of undesired variants. These results highlight some of the biochemical alterations that occur in banana trees with gigantism, providing a basis for future research on micropropagation programs and biofactories.