2LG1
Solution structure of the human AKAP13 PH domain and stabilizing DH helix
Summary for 2LG1
| Entry DOI | 10.2210/pdb2lg1/pdb |
| NMR Information | BMRB: 16195 |
| Descriptor | A-kinase anchor protein 13 (1 entity in total) |
| Functional Keywords | metal binding protein |
| Biological source | Homo sapiens (human) |
| Cellular location | Cytoplasm: Q12802 |
| Total number of polymer chains | 1 |
| Total formula weight | 21055.18 |
| Authors | Lenoir, M.,Sugawara, M.,Ball, L.,Overduin, M. (deposition date: 2011-07-19, release date: 2011-08-03, Last modification date: 2024-05-15) |
| Primary citation | Lenoir, M.,Sugawara, M.,Kaur, J.,Ball, L.J.,Overduin, M. Structural Insights into the Activation of the RhoA GTPase by the Lbc Oncoprotein. J.Biol.Chem., 3:215-218, 2014 Cited by PubMed Abstract: The small GTPase RhoA promotes deregulated signaling upon interaction with lymphoid blast crisis (Lbc), the oncogenic form of A-kinase anchoring protein 13 (AKAP13). 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 (1)H,(13)C,(15)N-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. PubMed: 24993829DOI: 10.1074/jbc.M114.561787 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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