The function of SRRM4 (serine/arginine repetitive matrix 4, ENSG00000139767) is as follows. Splicing factor specifically required for neural cell differentiation. Acts in conjunction with nPTB/PTBP2 by binding directly to its regulated target transcripts and promotes neural- specific exon inclusion in many genes that function in neural cell differentiation. Required to promote the inclusion of neural-specific exon 10 in nPTB/PTBP2, leading to increased expression of neural- specific nPTB/PTBP2. Also promotes the inclusion of exon 16 in DAAM1 in neuron extracts (By similarity). Promotes alternative splicing of REST transcripts to produce REST isoform 3 (REST4) with greatly reduced repressive activity, thereby activating expression of REST targets in neural cells (PubMed:30684677). Plays an important role during embryonic development as well as in the proper functioning of the adult nervous system. Regulates alternative splicing events in genes with important neuronal functions (By similarity). .