title: Plasticity of PI4KIIIα interactions at the plasma membrane.
abstract: Plasma membrane PI4P is an important direct regulator of many processes that occur at the plasma membrane and also a biosynthetic precursor of PI(4,5)P2 and its downstream metabolites. The majority of this PI4P pool is synthesized by an evolutionarily conserved complex, which has as its core the PI 4-kinase PI4KIIIα (Stt4 in yeast) and also comprises TTC7 (Ypp1 in yeast) and the peripheral plasma membrane protein EFR3. While EFR3 has been implicated in the recruitment of PI4KIIIα via TTC7, the plasma membrane protein Sfk1 was also shown to participate in this targeting and activity in yeast. Here, we identify a member of the TMEM150 family as a functional homologue of Sfk1 in mammalian cells and demonstrate a role for this protein in the homeostatic regulation of PI(4,5)P2 at the plasma membrane. We also show that the presence of TMEM150A strongly reduces the association of TTC7 with the EFR3-PI4KIIIα complex, without impairing the localization of PI4KIIIα at the plasma membrane. Collectively our results suggest a plasticity of the molecular interactions that control PI4KIIIα localization and function.
authors.affiliation: Department of Cell Biology, Howard Hughes Medical Institute Program in Cellular Neuroscience, Neurodegeneration and Repair Yale University Medical School, New Haven, CT, USA.
authors.forename: Jeeyun
authors.initials: J
authors.lastname: Chung
authors.affiliation: Department of Cell Biology, Howard Hughes Medical Institute Program in Cellular Neuroscience, Neurodegeneration and Repair Yale University Medical School, New Haven, CT, USA.
authors.forename: Fubito
authors.initials: F
authors.lastname: Nakatsu
authors.affiliation: Department of Cell Biology, Howard Hughes Medical Institute Program in Cellular Neuroscience, Neurodegeneration and Repair Yale University Medical School, New Haven, CT, USA.
authors.forename: Jeremy M
authors.initials: JM
authors.lastname: Baskin
authors.affiliation: Department of Cell Biology, Howard Hughes Medical Institute Program in Cellular Neuroscience, Neurodegeneration and Repair Yale University Medical School, New Haven, CT, USA pietro.decamilli@yale.edu.
authors.forename: Pietro
authors.initials: P
authors.lastname: De Camilli
mesh_terms: D002462:Cell Membrane / Q000378:metabolism*; D006367:HeLa Cells; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D015778:Minor Histocompatibility Antigens; D046912:Multiprotein Complexes / Q000378:metabolism*; D010454:Peptide Termination Factors / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism
chemical_list: D008565:Membrane Proteins; D015778:Minor Histocompatibility Antigens; D046912:Multiprotein Complexes; D010454:Peptide Termination Factors; D011506:Proteins; C000603328:TMEM150A protein, human; C583818:TTC7A protein, human; C087971:peptide-chain-release factor 3; D017853:Phosphotransferases (Alcohol Group Acceptor); C402182:phosphatidylinositol phosphate 4-kinase
keywords: PI4KA; Rolling blackout; Ypp1; phospholipase C