Cbp1p is a nuclear encoded protein required for the stabilization of mitochondrial COB mRNA, which codes for apocytochrome b in the yeast Saccharomyces cerevisiae. The COB gene is cotranscribed with the upstream tRNA(Glu) gene. Release of tRNA(Glu) from the initial transcript generates a precursor mRNA with a 5'-end at position -1098. The 5'-end of mature COB message is generated by cleavage of the pre-mRNA at nucleotide -955 or -954. Previous work indicated that Cbp1p acts through cis-elements near these cleavage sites. Here we have tested whether Cbp1p stabilizes COB mRNA solely by stimulating the processing of COB precursor RNA at nucleotide -955/-954. Yeast strain TG955 was constructed such that the -955 COB mRNA 5'-processing site coincides with the upstream tRNA 3'-endonuclease site at position -1098, allowing the 5'-end of COB mRNA to be formed by the tRNA 3'-processing enzyme. Respiratory growth and stability of COB mRNA in TG955 are Cbp1p-dependent. Therefore, we conclude that Cbp1p is important for the stabilization of COB mRNA after 5'-processing.

• PMID: 8206974
• PubMed
• PubTator

Reference Type

Journal Article | Research Support, Non-U.S. Gov't | Research Support, U.S. Gov't, P.H.S.

Authors

Chen W, Dieckmann CL

Primary Lit For

Additional Lit For

CBP1 | COB

Review For