Isolation and partial characterization of a 40 S ribosomal subunit-transfer ribonucleic acid binding factor from rabbit reticulocytes.
A factor that catalytically promotes the codon-directed, GTP-independent binding of tRNA to 40 S ribosomal subunits has been isolated from the postribosomal supernatant and the ribosomal wash of rabbit reticulocytes. The factor is a heat labile, sulfhydryl reagent-sensitive protein of a molecular weight of approximately 50,000. It consists of two non-identical subunits of Mr equals approximately 30,000 and 20,000. Its basic character has been confirmed by the high ratio of basic amino acids to nonamidic aspartic and glutamic acid present in the purified protein. Formation of a factor promoted 40 S-poly(U)-phenylalanyl-tRNA initiation complex causes a shift in the Mg-2+ concentration optimum for polyphenylalanine synthesis from 8 mM to 4mM.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001665:Binding Sites; D001798:Blood Proteins / Q000302:isolation & purification / Q000378:metabolism; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003062:Codon / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000494:pharmacology; D008274:Magnesium / Q000494:pharmacology; D008970:Molecular Weight; D010649:Phenylalanine / Q000378:metabolism; D011072:Poly U; D011485:Protein Binding; D014176:Protein Biosynthesis / Q000187:drug effects; D012335:RNA, Ribosomal / Q000097:blood / Q000378:metabolism*; D012343:RNA, Transfer / Q000097:blood / Q000378:metabolism*; D011817:Rabbits; D011955:Receptors, Drug; D012156:Reticulocytes / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*
D000596:Amino Acids; D001798:Blood Proteins; D003062:Codon; D012335:RNA, Ribosomal; D011955:Receptors, Drug; D011072:Poly U; D010649:Phenylalanine; D006160:Guanosine Triphosphate; D012343:RNA, Transfer; D008274:Magnesium