Enables mRNA binding activity. Involved in several processes, including negative regulation of cold-induced thermogenesis; regulation of alternative mRNA splicing, via spliceosome; and regulation of axon guidance. Acts upstream of or within regulation of RNA metabolic process. Is expressed in several structures, including central nervous system; lung; peripheral nervous system ganglion; retina; and trigeminal nerve. Orthologous to human NOVA2 (NOVA alternative splicing regulator 2). [provided by Alliance of Genome Resources, Apr 2022]