Predicted to enable RNA polymerase II complex binding activity and protein heterodimerization activity. Predicted to be involved in RNA metabolic process; chromatin organization; and regulation of transcription, DNA-templated. Predicted to be located in nucleoplasm. Predicted to be part of DSIF complex. Is expressed in brain; embryo; heart; and liver. Orthologous to human SUPT4H1 (SPT4 homolog, DSIF elongation factor subunit). [provided by Alliance of Genome Resources, Apr 2022]