The zinc finger transcription factor growth factor independence 1 (Gfi 1)

Growth Factor Independence I (Gfi 1) is a transcriptional repressor with a molecular weight between 47 and 55 kDa The protein has six C-terminal C2H2-type zinc-finger domains and a characteristic stretch of 20 amino acids, called the SNAG-domain, at its N-terminus. Expression of Gfi I ranges from the hematopoietic and lymphoid system, to sensory epithelia, lung and parts of the CNS. Gene knock-out studies revealed that Gfi I is essential for the development of granulocytes and plays a role in T-cell differentiation and macrophage-dependent cytokme production, indicating that this protein shares responsibility for different lines of defense against pathogens. Also, Gfi I is required for the proper development of inner ear hair cells illustrated by ataxia and deafness in knock-out mice. While hereditary hearing loss has so far not been associated with Gfi I malfunction, crippling mutations in the Gfi I gene have been reported in patients suffering from neutropenia suggesting an important role of Gfi I in this human disease. (C) 2004 Elsevier Ltd. All rights reserved.