Crystal structure of the human Rack1 protein at a resolution of 2.45 angstrom
[GBLP_HUMAN] Involved in the recruitment, assembly and/or regulation of a variety of signaling molecules. Interacts with a wide variety of proteins and plays a role in many cellular processes. Component of the 40S ribosomal subunit involved in translational repression. Binds to and stabilizes activated protein kinase C (PKC), increasing PKC-mediated phosphorylation. May recruit activated PKC to the ribosome, leading to phosphorylation of EIF6. Inhibits the activity of SRC kinases including SRC, LCK and YES1. Inhibits cell growth by prolonging the G0/G1 phase of the cell cycle. Enhances phosphorylation of BMAL1 by PRKCA and inhibits transcriptional activity of the BMAL1-CLOCK heterodimer. Facilitates ligand-independent nuclear translocation of AR following PKC activation, represses AR transactivation activity and is required for phosphorylation of AR by SRC. Modulates IGF1R-dependent integrin signaling and promotes cell spreading and contact with the extracellular matrix. Involved in PKC-dependent translocation of ADAM12 to the cell membrane. Promotes the ubiquitination and proteasome-mediated degradation of proteins such as CLEC1B and HIF1A. Required for VANGL2 membrane localization, inhibits Wnt signaling, and regulates cellular polarization and oriented cell division during gastrulation. Required for PTK2/FAK1 phosphorylation and dephosphorylation. Regulates internalization of the muscarinic receptor CHRM2. Promotes apoptosis by increasing oligomerization of BAX and disrupting the interaction of BAX with the anti-apoptotic factor BCL2L. Inhibits TRPM6 channel activity. Regulates cell surface expression of some GPCRs such as TBXA2R. Plays a role in regulation of FLT1-mediated cell migration. Binds to Y.pseudotuberculosis yopK which leads to inhibition of phagocytosis and survival of bacteria following infection of host cells. Enhances phosphorylation of HIV-1 Nef by PKCs. Promotes migration of breast carcinoma cells by binding to and activating RHOA.                  
Publication Abstract from PubMed
The crystal structure of human receptor for activated C-kinase 1 (hRack1) protein is reported at 2.45 A resolution. The crystals belongs to space group P4(1)2(1)2, with three molecules per asymmetric unit. The hRack1 structure features a sevenfold beta-propeller, with each blade housing a sequence motif that contains a strictly conserved Trp, the indole group of which is embedded between adjacent blades. In blades 1-5 the imidazole group of a His residue is wedged between the side chains of a Ser residue and an Asp residue through two hydrogen bonds. The hRack1 crystal structure forms a starting basis for understanding the remarkable scaffolding properties of this protein.
Structure of human Rack1 protein at a resolution of 2.45 A.,Ruiz Carrillo D, Chandrasekaran R, Nilsson M, Cornvik T, Liew CW, Tan SM, Lescar J Acta Crystallogr Sect F Struct Biol Cryst Commun. 2012 Aug 1;68(Pt 8):867-72., Epub 2012 Jul 26. PMID:22869111
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.