Enables transcription coregulator binding activity. Predicted to be involved in positive regulation of transcription, DNA-templated and regulation of transcription by RNA polymerase II. Predicted to act upstream of or within positive regulation of stem cell proliferation; positive regulation of transcription by RNA polymerase II; and regulation of stem cell population maintenance. Part of CCAAT-binding activity factor complex. Orthologous to human NFYA (nuclear transcription factor Y subunit alpha). [provided by Alliance of Genome Resources, Apr 2022]