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Updated: Aug 17, 2026

Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues
12:07

Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues

Published on: November 22, 2014

Initiation of synthesis of N-terminal acetylated histones with methionine

E Kecskes, I Sures, D Gallwitz

    Biochemistry
    |June 15, 1976
    PubMed

    Insights

    Histone synthesis begins with methionine, even though they have N-terminal acetylserine. This study confirms methionine initiation for N-terminal acetylated histones using specific labeling techniques.

    Area of Science:

    • Molecular Biology
    • Protein Synthesis
    • Epigenetics

    Background:

    • Histone synthesis is crucial for DNA packaging and gene regulation.
    • The initiation of histone synthesis, particularly those with N-terminal modifications, remained unclear.

    Purpose of the Study:

    • To determine if histone synthesis is initiated with methionine.
    • To investigate the role of methionine in the N-terminal acetylation of histones.

    Main Methods:

    • In vitro histone synthesis using rabbit reticulocyte lysate and ascites cell mRNA.
    • Labeling of N-termini with N-formyl[35S]methionine-tRNAfMet.
    • Analysis of tryptic peptides and Edman degradation.

    Main Results:

    • N-formylmethionine was incorporated into histones H1 and H4.
    • Comparison of labeled peptides confirmed methionine as the initiating amino acid.
    • N-terminal acetylated histones are initiated with methionine.

    Conclusions:

    • Histone synthesis is initiated with methionine, similar to other eukaryotic and bacterial proteins.
    • This clarifies the mechanism of N-terminal acetylation in histones.
    • Provides insight into the fundamental processes of protein initiation.

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