Basic Kruppel-like factor functions within a network of interacting haematopoietic transcription factors

Basic Kruppel-like Factor (BKLF) is a recently recognized member of a small group of transcription factors that bind CACCC motifs in DNA, by means of three highly conserved C-terminal Kruppel-like (typically Cys-X(2-4)Cys-X-12-His-X3-4-His) zinc fingers. Together with Erythroid Kruppel-like Factor (EKLF), it is one of the most abundant CACCC-binding proteins in erythroid cells. In contrast to EKLF, BKLF can act to repress transcription and thus may serve to moderate EKLF activity in vivo. Interestingly, it has also been shown that BKLF expression in erythroid cells is dependent on EKLF. Analysis of proteins interacting with BKLF indicates that it represses transcription by recruiting the general co-repressor protein CtBP, a cofactor that also associates with other haematopoietic transcriptional repressors such as Evi-1 and ZEB/AREB6. The observation that mice deficient in BKLF exhibit a myeloproliferative disorder suggests that BKLF regulates important processes involved in haematopoietic differentiation. (C) 1999 Elsevier Science Ltd. All rights reserved.