| Title: | "Tcn1p/Crz1p, a calcineurin-dependent transcription factor that differentially regulates gene expression in Saccharomyces cerevisiae" |
| Author(s): | Matheos DP; Kingsbury TJ; Ahsan US; Cunningham KW; |
| Address: | "Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218 USA" |
| ISSN/ISBN: | 0890-9369 (Print) 0890-9369 (Linking) |
| Abstract: | "Ca2+ signals regulate gene expression in animal and yeast cells through mechanisms involving calcineurin, a protein phosphatase activated by binding Ca2+ and calmodulin. Tcn1p, also named Crz1p, was identified as a transcription factor in yeast required for the calcineurin-dependent induction of PMC1, PMR1, PMR2A, and FKS2 which confer tolerance to high Ca2+, Mn2+, Na+, and cell wall damage, respectively. Tcn1p was not required for other calcineurin-dependent processes, such as inhibition of a vacuolar H+/Ca2+ exchanger and inhibition of a pheromone-stimulated Ca2+ uptake system, suggesting that Tcn1p functions downstream of calcineurin on a branch of the calcium signaling pathway leading to gene expression. Tcn1p contains three zinc finger motifs at its carboxyl terminus resembling the DNA-binding domains of Zif268, Swi5p, and other transcription factors. When fused to the transcription activation domain of Gal4p, the carboxy terminal domain of Tcn1p directed strong calcineurin-independent expression of PMC1-lacZ and other target genes. The amino-terminal domain of Tcn1p was found to function as a calcineurin-dependent transcription activation domain when fused to the DNA-binding domain of Gal4p. This amino-terminal domain also formed Ca2+-dependent and FK506-sensitive interactions with calcineurin in the yeast two-hybrid assay. These findings suggest that Tcn1p functions as a calcineurin-dependent transcription factor. Interestingly, induction of Tcn1p-dependent genes was found to be differentially controlled in response to physiological Ca2+ signals generated by treatment with mating pheromone and high salt. We propose that different promoters are sensitive to variations in the strength of Ca2+ signals generated by these stimuli and to effects of other signaling pathways" |
| Keywords: | "Amino Acid Sequence Binding Sites Calcineurin/*metabolism Calcium/metabolism Calcium-Transporting ATPases/genetics/metabolism DNA-Binding Proteins Fungal Proteins/genetics/metabolism *Gene Expression Regulation, Fungal Genes, Reporter *Glucosyltransferase;" |
| Notes: | "MedlineMatheos, D P Kingsbury, T J Ahsan, U S Cunningham, K W eng GM53082/GM/NIGMS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. 1998/02/07 Genes Dev. 1997 Dec 15; 11(24):3445-58. doi: 10.1101/gad.11.24.3445" |
