Interaction of bovine mitochondrial ribosomes with messenger RNA.
The gene for subunit II of cytochrome oxidase (CoII) from bovine mitochondria has been cloned behind a T7 promoter and the corresponding mRNA synthesized in vitro. The RNA transcribed from this vector has a single nucleotide 5' to the start AUG and, thus, corresponds closely to the native mRNA. It binds to the small 28 S ribosomal subunit of bovine mitochondria but not to the large (39 S) subunit or to 55 S ribosomes. The binding occurs readily in the absence of auxiliary initiation factors or initiator tRNA. The complex formed appears to contain 1 mRNA/28 S subunit. The observed binding is specific for mRNA since neither tRNA nor ribosomal RNA can act as competitive inhibitors. The interaction of the mRNA with the 28 S subunit does not require an AUG codon near the 5' end and constructs containing 5' leaders of more than 100 nucleotides still bind efficiently. About 5% of the bound mRNA is protected from digestion by T1 RNase. The protected fragments do not arise from a specific region of the mRNA since they hybridize to several restriction fragments of the cloned CoII gene.
Liao
H X
HX
Department of Chemistry, University of North Carolina, Chapel Hill 27599-3290.
Spremulli
L L
LL
D000818:Animals; D001665:Binding Sites; D002417:Cattle; D003576:Electron Transport Complex IV / Q000235:genetics; D066298:In Vitro Techniques; D008274:Magnesium / Q000378:metabolism; D008928:Mitochondria / Q000502:physiology*; D010442:Peptide Chain Initiation, Translational; D010448:Peptide Initiation Factors / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism*; D012343:RNA, Transfer / Q000502:physiology; D012270:Ribosomes / Q000378:metabolism* / Q000648:ultrastructure
D010448:Peptide Initiation Factors; D012333:RNA, Messenger; D012343:RNA, Transfer; D003576:Electron Transport Complex IV; D008274:Magnesium