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1gv7
From Proteopedia
ARH-I, an angiogenin/RNase A chimera
Structural highlights
Disease[ANGI_HUMAN] Defects in ANG are the cause of susceptibility to amyotrophic lateral sclerosis type 9 (ALS9) [MIM:611895]. ALS is a degenerative disorder of motor neurons in the cortex, brain stem and spinal cord. ALS is characterized by muscular weakness and atrophy.[1] [2] [3] [4] [5] [6] Function[ANGI_HUMAN] May function as a tRNA-specific ribonuclease that abolishes protein synthesis by specifically hydrolyzing cellular tRNAs. Binds to actin on the surface of endothelial cells; once bound, angiogenin is endocytosed and translocated to the nucleus. Angiogenin induces vascularization of normal and malignant tissues. Angiogenic activity is regulated by interaction with RNH1 in vivo.[7] [8] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAngiogenin and ribonuclease A share 33% sequence identity but have distinct functions. Angiogenin is a potent inducer of angiogenesis that is only weakly ribonucleolytic, whereas ribonuclease A is a robust ribonuclease that is not angiogenic. A chimera ("ARH-I"), in which angiogenin residues 58-70 are replaced with residues 59-73 of ribonuclease A, has intermediate ribonucleolytic potency and no angiogenic activity. Here we report a crystal structure of ARH-I that reveals the molecular basis for these characteristics. The ribonuclease A-derived (guest) segment adopts a structure largely similar to that in ribonuclease A, and successfully converts this region from a cell-binding site to a purine-binding site. At the same time, its presence causes complex changes in the angiogenin-derived (host) portion that account for much of the increased ribonuclease activity of ARH-I. Guest-host interactions of this type probably occur more generally in protein chimeras, emphasizing the importance of direct structural information for understanding the functional behavior of such molecules. Guest-host crosstalk in an angiogenin-RNase A chimeric protein.,Holloway DE, Shapiro R, Hares MC, Leonidas DD, Acharya KR Biochemistry. 2002 Aug 20;41(33):10482-9. PMID:12173935[9] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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