Comparative Proteomic Analysis of High-Temperature Response in Sugarcane (Saccharum spp.)

Plants exhibit complex molecular, physiological, and morphological responses to stress, which may be specific to the phenological phase of the crop. Knowledge of signalling cascades leading to the molecular and functional regulation of sugarcane in response to high-temperature stress is essential for the development of climate-resilient sugarcane varieties with stable expression of cane yield and quality under stress. In the present study, a comparative proteomic analysis was carried out with the commercial sugarcane variety Co 99004, which was established as tolerant to high-temperature stress based on evaluation of growth and physiological parameters. Proteins such as Poly[ADP-ribose] polymerase 2-B, REF/SRPP-like protein cpx, Putative F-box/kelch-repeat protein, Putative cyclin-dependent kinase F-2, Probable F-box protein, Thioredoxin O₂, Dirigent protein, MYB family transcription factor, stress-response A/B barrel domain, and Protein TIFY 11d were identified as high-temperature stress-responsive in the heat-tolerant variety Co 99004. These proteins showing differential expression patterns or function under high-temperature stress were revealed to be essential for plant survival, with diverse roles such as protection of intercellular proteins from denaturation, DNA repair and genome stability, alteration of membrane structure and composition, altogether ensuring sustained growth and cane yield under adverse environmental conditions. Further characterisation of the differentially expressed proteins and their gene functions might provide novel information to decipher the molecular mechanisms leading to the adaptation of sugarcane to high-temperature stress.