Perspective on Alternative Splicing and Proteome Complexity in Plants

Alternative splicing (AS) generates multiple transcripts from the same gene, however, AS contribution to proteome complexity remains elusive in plants. AS is prevalent under stress conditions in plants, but it is counterintuitive why plants would invest in protein synthesis under declining energy supply. We propose that plants employ AS not only to potentially increasing proteomic complexity, but also to buffer against the stress-responsive transcriptome to reduce the metabolic cost of translating all AS transcripts. To maximise efficiency under stress, plants may make fewer proteins with disordered domains via AS to diversify substrate specificity and maintain sufficient regulatory capacity. Furthermore, we suggest that chromatin state-dependent AS engenders short/long-term stress memory to mediate reproducible transcriptional response in the future. Stress-responsive alternative splicing (AS) modulates plant transcriptome but its contribution to proteome remains to be established. Intrinsically disordered proteins generated via AS may orchestrate additional/diversified substrate specificity under stress conditions to maintain regulatory capacity whilst keeping the metabolic cost of protein synthesis low. Translational coincidence can explain how plants adjust their proteome to prevailing photoperiods, hence optimising their metabolism and growth.