Title: | "The N-terminal 96 residues of MCM1, a regulator of cell type-specific genes in Saccharomyces cerevisiae, are sufficient for DNA binding, transcription activation, and interaction with alpha 1" |
Author(s): | Bruhn L; Hwang-Shum JJ; Sprague GF; |
Address: | "Institute of Molecular Biology, University of Oregon, Eugene 97403" |
DOI: | 10.1128/mcb.12.8.3563-3572.1992 |
ISSN/ISBN: | 0270-7306 (Print) 1098-5549 (Electronic) 0270-7306 (Linking) |
Abstract: | "MCM1 performs several functions necessary for its role in regulating cell type-specific gene expression in the yeast Saccharomyces cerevisiae: DNA binding, transcription activation, and interaction with coregulatory proteins such as alpha 1. We analyzed a set of MCM1 deletion derivatives using in vivo reporter gene assays and in vitro DNA-binding studies to determine which regions of MCM1 are important for its various activities. We also analyzed a set of LexA-MCM1 hybrids to examine the ability of different segments of MCM1 to activate transcription independent of MCM1's DNA-binding function. The first third of MCM1 [MCM1(1-96)], which includes an 80-residue segment homologous to the mammalian serum response factor, was sufficient for high-affinity DNA binding, for activation of reporter gene expression, and for interaction with alpha 1 in vitro and in vivo. However, the ability of MCM1(1-96) to activate transcription and to interact with alpha 1 was somewhat reduced compared with wild-type MCM1 [MCM1(1-286)]. Optimal interaction with alpha 1 required residues 99 to 117, in which 18 of 19 amino acids are acidic in character. Optimal transcription activation required a segment from residues 188 to 286, in which 50% of the amino acids are glutamine. Deletion of this segment from MCM1 reduced expression of reporter genes by about twofold. Moreover, LexA-MCM1 hybrids containing this segment were able to activate expression of reporter genes that rely on LexA binding sites as potential upstream activation sequences. Thus, glutamine-rich regions may contribute to the activation function of yeast transcription activators, as has been suggested for glutamine-rich mammalian proteins such as Sp1" |
Keywords: | "Bacterial Proteins/genetics/metabolism Chromosome Deletion DNA-Binding Proteins/*metabolism Fungal Proteins/genetics/isolation & purification/*metabolism *Gene Expression Regulation, Fungal *Genes, Fungal Kinetics Mating Factor Minichromosome Maintenance;" |
Notes: | "MedlineBruhn, L Hwang-Shum, J J Sprague, G F Jr eng GM07413/GM/NIGMS NIH HHS/ GM30027/GM/NIGMS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. 1992/08/11 Mol Cell Biol. 1992 Aug; 12(8):3563-72. doi: 10.1128/mcb.12.8.3563-3572.1992" |