HYPK controls stability and catalytic activity of the N-terminal acetyltransferase A in Arabidopsis thaliana.
Cell Rep
; 43(2): 113768, 2024 Feb 27.
Article
em En
| MEDLINE
| ID: mdl-38363676
ABSTRACT
The ribosome-tethered N-terminal acetyltransferase A (NatA) acetylates 52% of soluble proteins in Arabidopsis thaliana. This co-translational modification of the N terminus stabilizes diverse cytosolic plant proteins. The evolutionary conserved Huntingtin yeast partner K (HYPK) facilitates NatA activity in planta, but in vitro, its N-terminal helix α1 inhibits human NatA activity. To dissect the regulatory function of HYPK protein domains in vivo, we genetically engineer CRISPR-Cas9 mutants expressing a HYPK fragment lacking all functional domains (hypk-cr1) or an internally deleted HYPK variant truncating helix α1 but retaining the C-terminal ubiquitin-associated (UBA) domain (hypk-cr2). We find that the UBA domain of HYPK is vital for stabilizing the NatA complex in an organ-specific manner. The N terminus of HYPK, including helix α1, is critical for promoting NatA activity on substrates starting with various amino acids. Consequently, deleting only 42 amino acids inside the HYPK N terminus causes substantial destabilization of the plant proteome and higher tolerance toward drought stress.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arabidopsis
Limite:
Humans
Idioma:
En
Revista:
Cell Rep
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Alemanha