منابع مشابه
From elongator tRNA to initiator tRNA.
We show that the two most important properties needed for a tRNA to function in initiation in Escherichia coli are its ability to be formylated and its ability to bind to the ribosomal P site. This conclusion is based on conversion of two different elongator tRNAs to ones that can act as initiators in E. coli. We transplanted the features unique to E. coli and eubacterial initiator tRNAs to E. ...
متن کاملMutants of Escherichia coli formylmethionine tRNA: a single base change enables initiator tRNA to act as an elongator in vitro.
We show that the absence of a Watson-Crick base pair at the end of the amino acid acceptor stem, which is a hallmark of all prokaryotic initiator tRNAs, is one of the key features that prevents them from acting as an elongator in protein synthesis. We generated mutants of Escherichia coli formylmethionine tRNA that have a base pair at the end of the acceptor stem. The mutants generated were C1-...
متن کاملLocation alters tRNA identity: Trypanosoma brucei's cytosolic elongator tRNAMet is both the initiator and elongator in mitochondria.
A a rule, protein synthesis is initiated with methionine or formyl methionine from the first AUG codon in an ORF and that AUG is recognized by an initiator tRNAMet-i. Internal AUG codons are then translated by a second tRNA, the elongator tRNAMet-e (1). In eubacteria, mitochondria, and chloroplasts, the tRNAMet-i is charged with methionine, and subsequently the methionine is formylated by a met...
متن کاملConversion of aminoacylation specificity from tRNA to tRNA in vitro
The discrimination mechanism between tRNA" and tRNA* was studied using various in vitro transcripts of E. coli tRNATyr variants. The insertion of only two nucleotides into the variable stem of tRNAv generates serine charging activity. The acceptor activities of some of the tRNA? mutants with insertions in the long variable arm were enhanced by changes in nucleotides at positions 9 and/or 20B, w...
متن کاملP-site tRNA is a crucial initiator of ribosomal frameshifting.
The expression of some genes requires a high proportion of ribosomes to shift at a specific site into one of the two alternative frames. This utilized frameshifting provides a unique tool for studying reading frame control. Peptidyl-tRNA slippage has been invoked to explain many cases of programmed frameshifting. The present work extends this to other cases. When the A-site is unoccupied, the P...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1993
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.90.6.2305