IDENTIFICATION AND ANALYSIS OF A FUNCTIONAL HUMAN HOMOLOG OF THE SPT4GENE OF SACCHAROMYCES-CEREVISIAE

Spt4p is a nonhistone protein of Saccharomyces cerevisiae that is beli eved to be required for normal chromatin structure and transcription. In this work we describe the isolation and analysis of a human gene, S UPT4H, that encodes a predicted protein 42% identical to Spt4p. When e xpressed in S. cerevisiae, SUPT4H complemented all spt4 mutant phenoty pes. In human cells SUPT4H encodes a nuclear protein that is expressed in all tissues tested. In addition, hybridization analyses suggest th at an SUPT4H-related gene is also present in mice. SUPT4H was localize d to human chromosome 17 by PCR analysis of a human-rodent somatic cel l hybrid panel. Thus, like other proteins that are components of or co ntrol the structure of chromatin, Spt4p appears to be conserved from S . cerevisiae to mammals.