Single-stranded DNA-binding protein that preferentially binds to the sterol regulatory element (SRE) sequence 5'-GTGCGGTG-3', and thereby mediates transcriptional repression (By similarity). Has a role as transactivator of the Myc promoter (By similarity). Binds single-stranded RNA in a sequence-specific manner (By similarity). Binds G-rich elements in target mRNA coding sequences (By similarity). Prevents G-quadruplex structure formation in vitro, suggesting a role in supporting translation by resolving stable structures on mRNAs (By similarity). Associates with the 40S ribosomal subunit, the 80S ribosome and with polysomes.