Actin maturation requires the ACTMAP/C19orf54 protease

Peter Haahr, Ricardo A. Galli, Lisa G. van den Hengel, Onno B. Bleijerveld, Justina Kazokaite-Adomaitiene, Ji Ying Song, Lona J. Kroese, Paul Krimpenfort, Marijke P. Baltissen, Michiel Vermeulen, Coen A.C. Ottenheijm, Thijn R. Brummelkamp

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


Protein synthesis generally starts with a methionine that is removed during translation. However, cytoplasmic actin defies this rule because its synthesis involves noncanonical excision of the acetylated methionine by an unidentified enzyme after translation. Here, we identified C19orf54, named ACTMAP (actin maturation protease), as this enzyme. Its ablation resulted in viable mice in which the cytoskeleton was composed of immature actin molecules across all tissues. However, in skeletal muscle, the lengths of sarcomeric actin filaments were shorter, muscle function was decreased, and centralized nuclei, a common hallmark of myopathies, progressively accumulated. Thus, ACTMAP encodes the missing factor required for the synthesis of mature actin and regulates specific actin-dependent traits in vivo.

Original languageEnglish (US)
Pages (from-to)1533-1537
Number of pages5
Issue number6614
StatePublished - Sep 30 2022
Externally publishedYes

ASJC Scopus subject areas

  • General

Cite this