Association of yeast SAP1, a novel member of the ‘AAA’ ATPase family of proteins, with the chromatin protein SIN1

• Published in: FEBS letters 1996-06, Vol.388 (1), p.5-10
• Main Authors: Liberzon, Arthur, Shpungin, Sally, Bangio, Haim, Yona, Eyal, Katcoff, Don J.
• Format: Article
• Language: English
• Subjects: AAA; AAA family of ATPases; Adenosine Triphosphatases - genetics; Adenosine Triphosphatases - metabolism; Amino Acid Sequence; Base Sequence; Chromatin structure; Chromosomal Proteins, Non-Histone - genetics; Chromosomal Proteins, Non-Histone - metabolism; Cloning, Molecular; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Fungal Proteins - genetics; Fungal Proteins - metabolism; Genes, Fungal - genetics; Glutathione Transferase - genetics; Molecular Sequence Data; open reading frame; ORF; Protein Binding; Protein-protein interaction; Recombinant Fusion Proteins - metabolism; Saccharomyces cerevisiae; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae Proteins; Sequence Alignment; Sequence Analysis, DNA; SIN1/SPT2; SWI/SNF complex; TPases associated with diverse cellular activities; Transcriptional repression; UAS; upstream activating sequence
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(96)00500-5

The yeast SIN1 protein is a nuclear protein that together with other proteins behaves as a transcriptional repressor of a family of genes. In addition, sin1 mutants are defective in proper mitotic chromosome segregation. In an effort to understand the basis for these phenotypes, we employed the yeast two-hybrid system to identify proteins that interact with SIN1 in vivo. Here, we demonstrate that SAP1, a novel protein belonging to the ‘AAA’ family of ATPases, is able to directly interact with SIN1. Furthermore, we show, using recombinant molecules in vitro, that a short 27 amino acid sequence near the N-terminal of SIN1 is sufficient to bind SAP1. Previous experiments defined different domains of SIN that interact with other proteins and with DNA. The C-terminal domain of SIN1 was shown to be responsible for interaction with a protein that binds the regulatory region of HO, a gene whose transcription is repressed by SIN1. The central ‘HMG1-like region’ of SIN1 binds DNA, while the N-terminal of SIN1 can bind CDC23, a protein that regulates chromosome segregation. These data, taken together with the results presented here, suggest that SIN1 is a multifunctional chromatin protein that can interact with a number of different proteins that are involved in several different cellular functions.