%0 Journal Article %1 Humrich2005 %A Humrich, J. %A Bermel, C. %A Bunemann, M. %A Harmark, L. %A Frost, R. %A Quitterer, U. %A Lohse, M. J. %D 2005 %J J Biol Chem %K Acid Amino Base Binding Biological Carrier Casein Cell Chaperonin Chaperonins/*chemistry/genetics/*metabolism Complementary/genetics Complexes Containing DNA, Data Folding GTP-Binding Homology, Humans II/genetics/metabolism Interference Interfering/genetics Isoforms/chemistry/genetics/metabolism Kinase Line Models, Molecular Multiprotein Nerve Protein Proteins/chemistry/genetics/*metabolism Proteins/chemistry/genetics/metabolism RNA RNA, Recombinant Sequence Small Subunits Subunits/*chemistry/genetics/*metabolism TCP-1 Tissue beta gamma %N 20 %P 20042-50 %T Phosducin-like protein regulates G-protein betagamma folding by interaction with tailless complex polypeptide-1alpha: dephosphorylation or splicing of PhLP turns the switch toward regulation of Gbetagamma folding %U http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15745879 %V 280 %X Phosducin-like protein (PhLP) exists in two splice variants PhLP(LONG) (PhLP(L)) and PhLP(SHORT) (PhLP(S)). Whereas PhLP(L) directly inhibits Gbetagamma-stimulated signaling, the G betagamma-inhibitory mechanism of PhLP(S) is not understood. We report here that inhibition of Gbetagamma signaling in intact HEK cells by PhLP(S) was independent of direct Gbetagamma binding; however, PhLP(S) caused down-regulation of Gbeta and Ggamma proteins. The down-regulation was partially suppressed by lactacystine, indicating the involvement of proteasomal degradation. N-terminal fusion of Gbeta or Ggamma with a dye-labeling protein resulted in their stabilization against down-regulation by PhLP(S) but did not lead to a functional rescue. Moreover, in the presence of PhLP(S), stabilized Ggamma subunits did not coprecipitate with stabilized Gbeta subunits, suggesting that PhLP(S) might interfere with Gbetagamma folding. PhLP(S) and several truncated mutants of PhLP(S) interacted with the subunit tailless complex polypeptide-1alpha (TCP-1alpha) of the CCT chaperonin complex, which is involved in protein folding. Knock-down of TCP-1alpha in HEK cells by small interfering RNA also led to down-regulation of Gbetagamma. We therefore conclude that the strong inhibitory action of PhLP(S) on Gbetagamma signaling is the result of a previously unrecognized mechanism of Gbetagamma-regulation, inhibition of Gbetagamma-folding by interference with TCP-1alpha.

@article{Humrich2005, abstract = {Phosducin-like protein (PhLP) exists in two splice variants PhLP(LONG) (PhLP(L)) and PhLP(SHORT) (PhLP(S)). Whereas PhLP(L) directly inhibits Gbetagamma-stimulated signaling, the G betagamma-inhibitory mechanism of PhLP(S) is not understood. We report here that inhibition of Gbetagamma signaling in intact HEK cells by PhLP(S) was independent of direct Gbetagamma binding; however, PhLP(S) caused down-regulation of Gbeta and Ggamma proteins. The down-regulation was partially suppressed by lactacystine, indicating the involvement of proteasomal degradation. N-terminal fusion of Gbeta or Ggamma with a dye-labeling protein resulted in their stabilization against down-regulation by PhLP(S) but did not lead to a functional rescue. Moreover, in the presence of PhLP(S), stabilized Ggamma subunits did not coprecipitate with stabilized Gbeta subunits, suggesting that PhLP(S) might interfere with Gbetagamma folding. PhLP(S) and several truncated mutants of PhLP(S) interacted with the subunit tailless complex polypeptide-1alpha (TCP-1alpha) of the CCT chaperonin complex, which is involved in protein folding. Knock-down of TCP-1alpha in HEK cells by small interfering RNA also led to down-regulation of Gbetagamma. We therefore conclude that the strong inhibitory action of PhLP(S) on Gbetagamma signaling is the result of a previously unrecognized mechanism of Gbetagamma-regulation, inhibition of Gbetagamma-folding by interference with TCP-1alpha.}, added-at = {2010-12-14T18:12:02.000+0100}, author = {Humrich, J. and Bermel, C. and Bunemann, M. and Harmark, L. and Frost, R. and Quitterer, U. and Lohse, M. J.}, biburl = {https://www.bibsonomy.org/bibtex/2ea8035fc1add7d49b94b2584be96bb7f/pharmawuerz}, endnotereftype = {Journal Article}, interhash = {8a3ea97067d4b4483f74906c1523dcca}, intrahash = {ea8035fc1add7d49b94b2584be96bb7f}, issn = {0021-9258 (Print) 0021-9258 (Linking)}, journal = {J Biol Chem}, keywords = {Acid Amino Base Binding Biological Carrier Casein Cell Chaperonin Chaperonins/*chemistry/genetics/*metabolism Complementary/genetics Complexes Containing DNA, Data Folding GTP-Binding Homology, Humans II/genetics/metabolism Interference Interfering/genetics Isoforms/chemistry/genetics/metabolism Kinase Line Models, Molecular Multiprotein Nerve Protein Proteins/chemistry/genetics/*metabolism Proteins/chemistry/genetics/metabolism RNA RNA, Recombinant Sequence Small Subunits Subunits/*chemistry/genetics/*metabolism TCP-1 Tissue beta gamma}, month = {May 20}, note = {Humrich, Jan Bermel, Christina Bunemann, Moritz Harmark, Linda Frost, Robert Quitterer, Ursula Lohse, Martin J In Vitro United States The Journal of biological chemistry J Biol Chem. 2005 May 20;280(20):20042-50. Epub 2005 Mar 2.}, number = 20, pages = {20042-50}, shorttitle = {Phosducin-like protein regulates G-protein betagamma folding by interaction with tailless complex polypeptide-1alpha: dephosphorylation or splicing of PhLP turns the switch toward regulation of Gbetagamma folding}, timestamp = {2010-12-14T18:12:15.000+0100}, title = {Phosducin-like protein regulates G-protein betagamma folding by interaction with tailless complex polypeptide-1alpha: dephosphorylation or splicing of PhLP turns the switch toward regulation of Gbetagamma folding}, url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15745879}, volume = 280, year = 2005 }