PI(3,4,5)P3 Interactome

Abstract

Immobilizing chemically synthesized analogues of PI(3,4,5)P3 onto Affi-10 beads and incorporating them into liposomes allowed their use as affinity absorbents in the comprehensive analysis of the phosphoinositide interactome using cytosolic cell extracts of the LIM1215 colon cancer cell line. This led to the identification of 282 proteins that either interact with PI(3,4,5)P3 or are indirectly captured as part of a complex containing a PI(3,4,5)P3 binding partner. Identification of the proteins was achieved using affinity/LC-MS/MS experiments.

Identification of Dynamin-2-Mediated Endocytosis as a New Target of Osteoporosis Drugs, Bisphosphonates

“…Small unilamellar vesicles (SUVs) were prepared essentially as described previously (Sweitzer and Hinshaw, 1998;Catimel et al, 2009), in the following way: bovine total brain extract (Sigma-Aldrich, St. Louis, MO) was dissolved in chloroform/methanol (1:2). The solvent was evaporated, and lipid was redissolved in the appropriate buffer to a final concentration of 25 or 1 mg/ml by sonication.…”

Dropping in on the lipid droplet- tumor protein D52 (TPD52) as a new regulator and resident protein

“…Both TPD52 and TPD52L2 were identified as cholesterol-interacting proteins in HeLa cells, with both selectively binding a transsterol probe vs. a non-steroidal neutral lipid probe. 41 Furthermore, both TPD52 and TPD52L2 have been reported to bind the phosphoinositide PI(3,4,5)P3, 42 raising the possibility that a subset of TPD52-like proteins may bind lipid species directly.…”

Functional Proteomics: Mapping Lipid-Protein Interactomes

“…None of these proteins overlapped with the ones identified in the previous study. In a more comprehensive study, Holmes and colleagues have characterized and compared the interactomes of PtdIns(3,5)P 2 and PtdIns(4,5)P 2 (Catimel et al 2008) as well as PtdIns(3,4,5)P 3 (Catimel et al 2008;Catimel et al 2009) determined from the cytosolic extracts of colon cancer cells expressing WT PI3 kinase. PIs immobilized either onto beads or incorporated into liposomes were used for protein capture from the cytosolic extracts.…”

“…PIs immobilized either onto beads or incorporated into liposomes were used for protein capture from the cytosolic extracts. This led to the identification of 388 proteins in complex with PtdIns(3,5)P 2 and/or PtdIns(4,5)P 2 (Catimel et al 2008) and 282 proteins in complex with PtdIns(3,4,5)P 3 (Catimel et al 2009). A fraction of these were found to form complexes only with PtdIns(3,5)P 2 (69), PtdIns(4,5)P2 (146) or PtdIns(3,4,5)P 3 (141).…”