Activities, substrate specificity, and genetic interactions of fission yeast Siw14, a cysteinyl-phosphatase-type inositol pyrophosphatase.

ABSTRACT:

Importance

The inositol pyrophosphate signaling molecule 1,5-IP₈ modulates fission yeast phosphate homeostasis via its action as an agonist of RNA 3'-processing and transcription termination. Cellular 1,5-IP₈ levels are determined by a balance between the activities of the inositol polyphosphate kinase Asp1 and several inositol pyrophosphatase enzymes. Here, we characterize Schizosaccharomyces pombe Siw14 (SpSiw14) as a cysteinyl-phosphatase-family pyrophosphatase enzyme capable of hydrolyzing the phosphoanhydride substrates inorganic pyrophosphate, inorganic polyphosphate, and inositol pyrophosphates 5-IP₇, 1-IP₇, and 1,5-IP₈. Genetic analyses implicate SpSiw14 in 1,5-IP₈ catabolism in vivo, insofar as

SUBMITTER: Sanchez AM 

PROVIDER: S-EPMC10653929 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature