VIP1 (YLR410W) notes

UniProt Q06685, bifunctional PPIP5K: N-terminal ATP-grasp InsP6/InsP7 1-kinase (EC 2.7.4.24) and C-terminal histidine-acid-phosphatase-like domain [UniProt:Q06685].

Kinase

• Identified as an IP6/IP7 kinase PMID:17412958. The 2007 paper originally assigned the new pyrophosphate to the 4/6 position.
• Positional specificity corrected to the 1/3 position (enantiomers not resolved in that work); UniProt and later literature give position 1 PMID:18981179; with Kcs1 (IP6K) it makes 1,5-(PP)2-IP4 PMID:18981179.
• => GO:0000830 (4-kinase) and GO:0000831 (6-kinase) IDA rows from PMID:17412958 are contradicted; GO:0052724 (3-kinase) reflects the unresolved enantiomer.

Phosphatase domain

• Despite the UniProt CAUTION (predicted inactive), the isolated ScVip1 phosphatase domain is an active inositol pyrophosphate phosphatase PMID:39966396; also in PMID:31436531. Pi inhibits the phosphatase PMID:31436531.

Phosphate signalling

• vip1 extracts fail to support Pho81-dependent inhibition of Pho80-Pho85 PMID:17412959.

Location

• Cytoplasm (GFP; Huh et al.) [UniProt:Q06685]. Cytoskeleton call also from GFP screen; weak.

ISS rows from S. pombe Asp1

• "regulation of bipolar cell growth" and "regulation of microtubule cytoskeleton organization" are transferred from Asp1 (O74429); fission-yeast-specific growth mode, no S. cerevisiae data.