The zebrafish klf gene family

The Kroppel-like factor (KLF) family of genes encodes transcriptional regul atory proteins that play roles in differentiation of a diverse set of cells in mammals. For instance, the founding member KLF1 (also known as EKLF) is required for normal globin production in mammals. Five new KLF genes have been isolated from the zebrafish, Danio rerio, and the structure of their p roducts, their genetic map positions, and their expression during developme nt of the zebrafish have been characterized. Three genes closely related to mammalian KLF2 and KLF4 were found, as was an ortholog of mammalian KLF12. A fifth gene, apparently missing from the genome of mammals and closely re lated to KLF1 and KLF2, was also identified. Analysis demonstrated the exis tence of novel conserved domains in the N-termini of these proteins. Develo pmental expression patterns suggest potential roles for these zebrafish gen es in diverse processes, including hematopoiesis, blood vessel function, an d fin and epidermal development. The studies imply a high degree of functio nal conservation of the zebrafish genes with their mammalian homologs. Thes e findings further the understanding of the KLF genes in vertebrate develop ment and indicate an ancient role in hematopoiesis for the Kroppel-like fac tor gene family. (C) 2001 by The American Society of Hematology.