Transcriptional activator which binds specifically to the MEF2 element; 5'-YTA[AT](4)TAR-3'; found in numerous muscle- specific genes. Also involved in the activation of numerous growth factor- and stress-induced genes. Mediates cellular functions not only in skeletal and cardiac muscle development; but also in neuronal differentiation and survival. Plays diverse roles in the control of cell growth; survival and apoptosis via p38 MAPK signaling in muscle-specific and/or growth factor-related transcription. In cerebellar granule neurons; phosphorylated and sumoylated MEF2A represses transcription of NUR77 promoting synaptic differentiation. Associates with chromatin to the ZNF16 promoter. {ECO:0000269|PubMed:11904443; ECO:0000269|PubMed:12691662; ECO:0000269|PubMed:15834131; ECO:0000269|PubMed:16371476; ECO:0000269|PubMed:16484498; ECO:0000269|PubMed:16563226; ECO:0000269|PubMed:21468593; ECO:0000269|PubMed:9858528}.