Protein expression profiling at different developmental stages of ploidy series of guinea grass (Megathyrsus maximus)

Abstract

Guinea grass (Megathyrsus maximus (Jacq.) Simon & Jacobs.) exhibits wide ploidy variation and diverse reproductive behavior, making it a valuable model for studying protein expression dynamics during reproductive development. In the present study, protein expression profiles were comparatively analyzed across different developmental stages and ploidy levels of M. maximus using SDS-PAGE as a preliminary profiling approach. A diverse ploidy series (3x, 4x, 5x, 6x, 7x, 8x, 9x and 11x) derived from a 4x progenitor was evaluated at pre-meiotic, meiotic, and post-meiotic stages. Protein extraction from inflorescence tissue followed by SDS-PAGE analysis identified protein polymorphism across ploidy levels and developmental stages, revealing stage-specific and ploidy-dependent variations in protein expression. The meiotic stage exhibited the highest protein polymorphism, suggesting an active meiotic regulation, while the post-meiotic stage showed a decline in meiosis-specific proteins, indicating regulatory transitions in gamete maturation. Higher ploidy levels (7x, 8x, 9x and 11x) demonstrated greater protein polymorphism, suggesting ploidy-dependent regulation of meiosis-associated proteins. Cluster analysis, based on Jaccard’s similarity coefficient, grouped samples according to similarity in protein banding patterns across developmental stages and ploidy levels. The findings provide a comparative description of protein expression variation associated with reproductive development and ploidy differences in guinea grass and establish a baseline for future studies employing advanced proteomic and functional validation approaches.