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| | ==Solution structure of the human AKAP13 PH domain and stabilizing DH helix== | | ==Solution structure of the human AKAP13 PH domain and stabilizing DH helix== |
| - | <StructureSection load='2lg1' size='340' side='right' caption='[[2lg1]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''> | + | <StructureSection load='2lg1' size='340' side='right'caption='[[2lg1]]' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | [[2lg1]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LG1 OCA]. <br> | + | <table><tr><td colspan='2'>[[2lg1]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LG1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2LG1 FirstGlance]. <br> |
| - | <b>Activity:</b> <span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span><br> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</td></tr> |
| - | <b>Resources:</b> <span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2lg1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2lg1 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2lg1 RCSB], [http://www.ebi.ac.uk/pdbsum/2lg1 PDBsum]</span><br> | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2lg1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2lg1 OCA], [https://pdbe.org/2lg1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2lg1 RCSB], [https://www.ebi.ac.uk/pdbsum/2lg1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2lg1 ProSAT]</span></td></tr> |
| | + | </table> |
| | + | == Function == |
| | + | [https://www.uniprot.org/uniprot/AKP13_HUMAN AKP13_HUMAN] Anchors cAMP-dependent protein kinase (PKA) and acts as an adapter protein to selectively couple G alpha-13 and Rho. Augments gene activation by the estrogen receptor in an element-specific and ligand-dependent manner. Activates estrogen receptor beta by a p38 MAPK-dependent pathway. Stimulates exchange activity on Rho proteins in vitro, but not on CDC42, Ras or Rac and may bind calcium ions.<ref>PMID:11546812</ref> <ref>PMID:9627117</ref> <ref>PMID:9891067</ref> <ref>PMID:11579095</ref> |
| | + | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
| - | The human AKAP13 protein contains DH and PH domains, which are responsible for its cell transforming activity. Despite its biomedical importance, the contribution of the PH domain to AKAP13 activity remains unclear and no three dimensional structure is available to date. Here we report the backbone and side chain (1)H, (13)C and (15)N resonance assignments of a 20 kDa construct comprising the uniformly (13)C and( 15)N labeled AKAP13-PH domain and an associated helix from the DH domain which is required for its stable expression. Resonance assignment has been achieved using conventional triple resonance experiments; 95% of all back bone resonances and more than 90% of side chain resonances have been successfully assigned. The (1)H, (13)C and (15)N chemical shifts have been deposited in BMRB with accession number of 16195. | + | The small GTPase RhoA promotes deregulated signalling upon interaction with Lbc, the oncogenic form of A-kinase anchoring protein (AKAP). The onco-Lbc protein is a hyperactive Rho-specific guanine nucleotide exchange factor (GEF), but its structural mechanism has not been reported, despite its involvement in cardiac hypertrophy and cancer causation. The pleckstrin homology (PH) domain of Lbc is located at the C-terminal end of the protein, and is shown here to specifically recognize activated RhoA rather than lipids. The isolated dbl homology (DH) domain can function as an independent activator with an enhanced activity. However, the DH domain normally does not act as a solitary Lbc interface with RhoA-GDP. Instead it is negatively controlled by the PH domain. In particular the DH helical bundle is coupled to the structurally dependent PH domain through a helical linker, which reduces its activity. Together the two domains form a rigid scaffold in solution, as evidenced by small angle X-ray scattering and 1H,13C,15N-based NMR spectroscopy. The two domains assume a "chair" shape, with its back possessing independent GEF activity, and the PH domain providing a broad seat for RhoA-GTP docking rather than membrane recognition. This provides structural and dynamical insights into how DH and PH domains work together in solution to support regulated RhoA activity. Mutational analysis supports the bifunctional PH domain mediation of DH:RhoA interactions and explains why the tandem domain is required for controlled GEF signaling. |
| | + | |
| | + | Structural Insights into the Activation of the RhoA GTPase by the Lbc Oncoprotein.,Lenoir M, Sugawara M, Kaur J, Ball LJ, Overduin M J Biol Chem. 2014 Jul 3. pii: jbc.M114.561787. PMID:24993829<ref>PMID:24993829</ref> |
| | | | |
| - | Resonance assignments of the human AKAP13-PH domain and stabilizing DH helix.,Sugawara M, Whittaker SB, Bishop S, Ball L, Overduin M Biomol NMR Assign. 2009 Dec;3(2):215-8. Epub 2009 Jul 18. PMID:19888694<ref>PMID:19888694</ref>
| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> |
| | + | </div> |
| | + | <div class="pdbe-citations 2lg1" style="background-color:#fffaf0;"></div> |
| | | | |
| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
| + | ==See Also== |
| | + | *[[A-kinase anchor protein 3D structures|A-kinase anchor protein 3D structures]] |
| | == References == | | == References == |
| | <references/> | | <references/> |
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| | </StructureSection> | | </StructureSection> |
| | [[Category: Homo sapiens]] | | [[Category: Homo sapiens]] |
| - | [[Category: Ball, L.]] | + | [[Category: Large Structures]] |
| - | [[Category: Lenoir, M.]] | + | [[Category: Ball L]] |
| - | [[Category: Overduin, M.]] | + | [[Category: Lenoir M]] |
| - | [[Category: Sugawara, M.]] | + | [[Category: Overduin M]] |
| - | [[Category: Metal binding protein]] | + | [[Category: Sugawara M]] |
| Structural highlights
Function
AKP13_HUMAN Anchors cAMP-dependent protein kinase (PKA) and acts as an adapter protein to selectively couple G alpha-13 and Rho. Augments gene activation by the estrogen receptor in an element-specific and ligand-dependent manner. Activates estrogen receptor beta by a p38 MAPK-dependent pathway. Stimulates exchange activity on Rho proteins in vitro, but not on CDC42, Ras or Rac and may bind calcium ions.[1] [2] [3] [4]
Publication Abstract from PubMed
The small GTPase RhoA promotes deregulated signalling upon interaction with Lbc, the oncogenic form of A-kinase anchoring protein (AKAP). The onco-Lbc protein is a hyperactive Rho-specific guanine nucleotide exchange factor (GEF), but its structural mechanism has not been reported, despite its involvement in cardiac hypertrophy and cancer causation. The pleckstrin homology (PH) domain of Lbc is located at the C-terminal end of the protein, and is shown here to specifically recognize activated RhoA rather than lipids. The isolated dbl homology (DH) domain can function as an independent activator with an enhanced activity. However, the DH domain normally does not act as a solitary Lbc interface with RhoA-GDP. Instead it is negatively controlled by the PH domain. In particular the DH helical bundle is coupled to the structurally dependent PH domain through a helical linker, which reduces its activity. Together the two domains form a rigid scaffold in solution, as evidenced by small angle X-ray scattering and 1H,13C,15N-based NMR spectroscopy. The two domains assume a "chair" shape, with its back possessing independent GEF activity, and the PH domain providing a broad seat for RhoA-GTP docking rather than membrane recognition. This provides structural and dynamical insights into how DH and PH domains work together in solution to support regulated RhoA activity. Mutational analysis supports the bifunctional PH domain mediation of DH:RhoA interactions and explains why the tandem domain is required for controlled GEF signaling.
Structural Insights into the Activation of the RhoA GTPase by the Lbc Oncoprotein.,Lenoir M, Sugawara M, Kaur J, Ball LJ, Overduin M J Biol Chem. 2014 Jul 3. pii: jbc.M114.561787. PMID:24993829[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Diviani D, Soderling J, Scott JD. AKAP-Lbc anchors protein kinase A and nucleates Galpha 12-selective Rho-mediated stress fiber formation. J Biol Chem. 2001 Nov 23;276(47):44247-57. Epub 2001 Sep 6. PMID:11546812 doi:http://dx.doi.org/10.1074/jbc.M106629200
- ↑ Rubino D, Driggers P, Arbit D, Kemp L, Miller B, Coso O, Pagliai K, Gray K, Gutkind S, Segars J. Characterization of Brx, a novel Dbl family member that modulates estrogen receptor action. Oncogene. 1998 May 14;16(19):2513-26. PMID:9627117 doi:http://dx.doi.org/10.1038/sj.onc.1201783
- ↑ Sterpetti P, Hack AA, Bashar MP, Park B, Cheng SD, Knoll JH, Urano T, Feig LA, Toksoz D. Activation of the Lbc Rho exchange factor proto-oncogene by truncation of an extended C terminus that regulates transformation and targeting. Mol Cell Biol. 1999 Feb;19(2):1334-45. PMID:9891067
- ↑ Driggers PH, Segars JH, Rubino DM. The proto-oncoprotein Brx activates estrogen receptor beta by a p38 mitogen-activated protein kinase pathway. J Biol Chem. 2001 Dec 14;276(50):46792-7. Epub 2001 Sep 28. PMID:11579095 doi:http://dx.doi.org/10.1074/jbc.M106927200
- ↑ Lenoir M, Sugawara M, Kaur J, Ball LJ, Overduin M. Structural Insights into the Activation of the RhoA GTPase by the Lbc Oncoprotein. J Biol Chem. 2014 Jul 3. pii: jbc.M114.561787. PMID:24993829 doi:http://dx.doi.org/10.1074/jbc.M114.561787
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