Initiation of Rabbit Hemoglobin Synthesis: Methionine and Formylmethionine at the N-Terminal*
AUTOR(ES)
Yoshida, Akira
RESUMO
Ribosome-bound peptides were prepared from rabbit reticulocytes incubated in a reaction mixture that contained all essential amino acids except tryptophan. The peptides were fractionated by Sephadex gel filtration and the N-termini of these peptides were examined. Longer uncompleted hemoglobin chains (larger than 30 amino acids) had unblocked valine at the N-terminal position. In contrast, shorter initial parts of chains (smaller than 16 amino acids) did not have valine at the N-terminal position. These small peptides had methionine at the N-terminal, and 8% of the terminal methionine was presumably formylated. These findings indicate that hemoglobin chains are initiated from methionine or N-formylmethionine (or from both methionine and N-formylmethionine), and that the methionyl residue is hydrolyzed at an early stage of chain elongation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=283396Documentos Relacionados
- Length recognition at the N-terminal tail for the initiation of FtsH-mediated proteolysis
- N-terminal methionine-specific peptidase in Salmonella typhimurium.
- Control of protein life-span by N-terminal methionine excision
- Further studies on the initiation of protein synthesis with N-formylmethionine in E. coli extracts.
- Gαs is palmitoylated at the N-terminal glycine