title: Ca2+-calmodulin inhibits tail-anchored protein insertion into the mammalian endoplasmic reticulum membrane.
abstract: Cytosolic components and pathways have been identified that are involved in inserting tail-anchored (TA) membrane proteins into the yeast or mammalian endoplasmic reticulum (ER) membrane. Searching for regulatory mechanisms of TA protein biogenesis, we found that Ca(2+)-calmodulin (CaM) inhibits the insertion of TA proteins into mammalian ER membranes and that this inhibition is prevented by trifluoperazine, a CaM antagonist that interferes with substrate binding of Ca(2+)-CaM. The effects of Ca(2+)-CaM on cytochrome b(5) and Synaptobrevin 2 suggest a direct interaction between Ca(2+)-CaM and TA proteins. Thus, CaM appears to regulate TA insertion into the ER membrane in a Ca(2+) dependent manner.
authors: Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany.
authors: Sarah
authors: S
authors: Hassdenteufel
authors: Nico
authors: N
authors: Schäuble
authors: Patrizia
authors: P
authors: Cassella
authors: Pawel
authors: P
authors: Leznicki
authors: Anika
authors: A
authors: Müller
authors: Stephen
authors: S
authors: High
authors: Martin
authors: M
authors: Jung
authors: Richard
authors: R
authors: Zimmermann
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002147:Calmodulin / Q000494:pharmacology*; D002417:Cattle; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000187:drug effects* / Q000378:metabolism*; D007425:Intracellular Membranes / Q000187:drug effects* / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008861:Microsomes / Q000187:drug effects / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D011817:Rabbits
chemical_list: D002147:Calmodulin; D008565:Membrane Proteins; D002118:Calcium