Calcium- and myristoyl-dependent subcellular localization of the neuronal calcium-binding protein VILIP in transfected PC12 cells.
Wild-type neuronal calcium-binding protein VILIP (visinin-like protein), and a myristoylation mutant of VILIP which lacks the consensus sequence for N-terminal myristoylation, have been stably transfected in PC12 cells. Immunocytochemical studies of VILIP-transfected PC12 cells have revealed the wild-type VILIP is strongly concentrated at the cell membrane, particularly at cell-cell contact sites, but is also distributed throughout the cytosol at moderate levels. In contrast, myristoylation-mutant VILIP shows a more even distribution, with significantly less association at cell-cell contact sites. Western blot analysis of subcellular fractions has shown that wild-type VILIP associates in a calcium-dependent manner with membrane fractions, whereas the myristoylation mutant only weakly associates with this fraction. Therefore, a calcium-myristoyl switch seems to be a major, but not sole determinant for the association of VILIP with membranes in living cells.
Spilker
C
C
Department of Molecular Biology and Neurochemistry, Federal Institute for Neurobiology, Magdeburg, Germany.
Gundelfinger
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ED
Braunewell
K H
KH
D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D007150:Immunohistochemistry; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D051596:Neurocalcin; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D016716:PC12 Cells / Q000378:metabolism*; D051381:Rats; D044169:Receptors, Calcium-Sensing; D014162:Transfection
D002135:Calcium-Binding Proteins; D009419:Nerve Tissue Proteins; D051596:Neurocalcin; D044169:Receptors, Calcium-Sensing; C496690:Vsnl1 protein, rat; D002118:Calcium