Enables supercoiled DNA binding activity. Predicted to be involved in several processes, including mRNA 5'-splice site recognition; positive regulation of transcription by RNA polymerase II; and response to heat. Located in heterochromatin and transcriptionally active chromatin. Orthologous to human PSIP1 (PC4 and SFRS1 interacting protein 1). [provided by Alliance of Genome Resources, Apr 2022]