HYPK promotes the activity of the Nα-acetyltransferase A complex to determine proteostasis of nonAc-X2/N-degron-containing proteins.
Sci Adv
; 8(24): eabn6153, 2022 06 17.
Article
en En
| MEDLINE
| ID: mdl-35704578
ABSTRACT
In humans, the Huntingtin yeast partner K (HYPK) binds to the ribosome-associated Nα-acetyltransferase A (NatA) complex that acetylates ~40% of the proteome in humans and Arabidopsis thaliana. However, the relevance of HsHYPK for determining the human N-acetylome is unclear. Here, we identify the AtHYPK protein as the first in vivo regulator of NatA activity in plants. AtHYPK physically interacts with the ribosome-anchoring subunit of NatA and promotes Nα-terminal acetylation of diverse NatA substrates. Loss-of-AtHYPK mutants are remarkably resistant to drought stress and strongly resemble the phenotype of NatA-depleted plants. The ectopic expression of HsHYPK rescues this phenotype. Combined transcriptomics, proteomics, and N-terminomics unravel that HYPK impairs plant metabolism and development, predominantly by regulating NatA activity. We demonstrate that HYPK is a critical regulator of global proteostasis by facilitating masking of the recently identified nonAc-X2/N-degron. This N-degron targets many nonacetylated NatA substrates for degradation by the ubiquitin-proteasome system.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Arabidopsis
/
Acetiltransferasa A N-Terminal
Idioma:
En
Revista:
Sci Adv
Año:
2022
Tipo del documento:
Article
País de afiliación:
Alemania