Transcription factor that activates expression from GC-rich minimal promoter regions, including genes in the cells of the erythroid lineage (By similarity). Represses transcription by binding to the BTE site, a GC-rich DNA element, in competition with the activator SP1. It also represses transcription by interacting with the corepressor Sin3A and HDAC1 (PubMed:11477107). Activates RANTES and CCL5 expression in T- cells (PubMed:17513757). {ECO:0000250|UniProtKB:Q9JJZ6, ECO:0000269|PubMed:11477107, ECO:0000269|PubMed:17513757}. This is the function of ENSG00000169926 (KLF13, KLF transcription factor 13).