The X-linked zinc finger protein ZFX is a member of the Kruppel C2H2-type zinc-finger protein family. The full-length protein contains an acidic transcriptional activation domain (AD), a nuclear localization sequence (NLS) and a DNA binding domain (DBD) consisting of 13 C2H2-type zinc fingers. Studies in mouse embryonic and adult hematopoietic stem cells showed that this gene was required as a transcriptional regulator for self-renewal of both stem cell types, but it was dispensable for growth and differentiation of their progeny.