2n46
EC-NMR Structure of Human H-RasT35S mutant protein Determined by Combining Evolutionary Couplings (EC) and Sparse NMR DataEC-NMR Structure of Human H-RasT35S mutant protein Determined by Combining Evolutionary Couplings (EC) and Sparse NMR Data
Structural highlights
Disease[RASH_HUMAN] Defects in HRAS are the cause of faciocutaneoskeletal syndrome (FCSS) [MIM:218040]. A rare condition characterized by prenatally increased growth, postnatal growth deficiency, mental retardation, distinctive facial appearance, cardiovascular abnormalities (typically pulmonic stenosis, hypertrophic cardiomyopathy and/or atrial tachycardia), tumor predisposition, skin and musculoskeletal abnormalities.[1] [2] [3] [4] [5] [6] [7] Defects in HRAS are the cause of congenital myopathy with excess of muscle spindles (CMEMS) [MIM:218040]. CMEMS is a variant of Costello syndrome.[8] Defects in HRAS may be a cause of susceptibility to Hurthle cell thyroid carcinoma (HCTC) [MIM:607464]. Hurthle cell thyroid carcinoma accounts for approximately 3% of all thyroid cancers. Although they are classified as variants of follicular neoplasms, they are more often multifocal and somewhat more aggressive and are less likely to take up iodine than are other follicular neoplasms. Note=Mutations which change positions 12, 13 or 61 activate the potential of HRAS to transform cultured cells and are implicated in a variety of human tumors. Defects in HRAS are a cause of susceptibility to bladder cancer (BLC) [MIM:109800]. A malignancy originating in tissues of the urinary bladder. It often presents with multiple tumors appearing at different times and at different sites in the bladder. Most bladder cancers are transitional cell carcinomas. They begin in cells that normally make up the inner lining of the bladder. Other types of bladder cancer include squamous cell carcinoma (cancer that begins in thin, flat cells) and adenocarcinoma (cancer that begins in cells that make and release mucus and other fluids). Bladder cancer is a complex disorder with both genetic and environmental influences. Note=Defects in HRAS are the cause of oral squamous cell carcinoma (OSCC).[9] Defects in HRAS are the cause of Schimmelpenning-Feuerstein-Mims syndrome (SFM) [MIM:163200]. A disease characterized by sebaceous nevi, often on the face, associated with variable ipsilateral abnormalities of the central nervous system, ocular anomalies, and skeletal defects. Many oral manifestations have been reported, not only including hypoplastic and malformed teeth, and mucosal papillomatosis, but also ankyloglossia, hemihyperplastic tongue, intraoral nevus, giant cell granuloma, ameloblastoma, bone cysts, follicular cysts, oligodontia, and odontodysplasia. Sebaceous nevi follow the lines of Blaschko and these can continue as linear intraoral lesions, as in mucosal papillomatosis.[10] Function[RASH_HUMAN] Ras proteins bind GDP/GTP and possess intrinsic GTPase activity.[11] [12] [13] Publication Abstract from PubMedRas small GTPases undergo dynamic equilibrium of two interconverting conformations, state 1 and state 2, in the GTP-bound forms, where state 2 is recognized by effectors, whereas physiological functions of state 1 have been unknown. Limited information, such as static crystal structures and (31)P NMR spectra, was available for the study of the conformational dynamics. Here we determine the solution structure and dynamics of state 1 by multidimensional heteronuclear NMR analysis of an H-RasT35S mutant in complex with guanosine 5'-(beta, gamma-imido)triphosphate (GppNHp). The state 1 structure shows that the switch I loop fluctuates extensively compared with that in state 2 or H-Ras-GDP. Also, backbone (1)H,(15)N signals for state 2 are identified, and their dynamics are studied by utilizing a complex with c-Raf-1. Furthermore, the signals for almost all the residues of H-Ras.GppNHp are identified by measurement at low temperature, and the signals for multiple residues are found split into two peaks corresponding to the signals for state 1 and state 2. Intriguingly, these residues are located not only in the switch regions and their neighbors but also in the rigidly structured regions, suggesting that global structural rearrangements occur during the state interconversion. The backbone dynamics of each state show that the switch loops in state 1 are dynamically mobile on the picosecond to nanosecond time scale, and these mobilities are significantly reduced in state 2. These results suggest that multiconformations existing in state 1 are mostly deselected upon the transition toward state 2 induced by the effector binding. Solution structure of the state 1 conformer of GTP-bound H-Ras protein and distinct dynamic properties between the state 1 and state 2 conformers.,Araki M, Shima F, Yoshikawa Y, Muraoka S, Ijiri Y, Nagahara Y, Shirono T, Kataoka T, Tamura A J Biol Chem. 2011 Nov 11;286(45):39644-53. Epub 2011 Sep 19. PMID:21930707[14] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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