title: Proteins of the 30-S subunit of Escherichia coli ribosomes which interact directly with natural mRNA.
abstract: Ultraviolet irradiation (254 nm) of the complexes of MS2 phage RNA (mRNA) and the 30-S subunits of Escherichia coli ribosomes prepared at 0 degrees C and 37 degrees C in the presence and absence of initiation factor 3 (IF-3) causes cross-linking of mRNA with proteins S3, S4, S5, S7, S9, S18 and IF-3. Hence, these proteins interact directly with mRNA within the complex 30-S-subunit . mRNA. Addition of IF-3 results in an increase of the rate of complex formation and decrease of its dissociation rate. The addition of IF-3 changes the relative amounts of cross-linked proteins (mainly S3, S4 and S18). Decreasing the temperature from 37 degrees C to 0 degrees C not only decelerates the complex formation rate but also changes the relative amount of cross-linked proteins, indicating the influence of the conditions on the structure of the complex.
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D055598:Chemical Phenomena; D002621:Chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D007700:Kinetics; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000378:metabolism* / Q000528:radiation effects; D013696:Temperature; D014466:Ultraviolet Rays
chemical_list: D001426:Bacterial Proteins; D012333:RNA, Messenger; D012269:Ribosomal Proteins