Assembly of an evolutionarily conserved alternative proteasome isoform in human cells

Targeted intracellular protein degradation in eukaryotes is largely mediated by the proteasome. Here, we report the formation of an alternative proteasome isoform in human cells, previously found only in budding yeast, that bears an altered subunit arrangement in the outer ring of the proteasome cor...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Padmanabhan, Achuth (VerfasserIn) , Vuong, Simone (VerfasserIn) , Hochstrasser, Mark (VerfasserIn)
Dokumenttyp: Article (Journal)
Sprache:Englisch
Veröffentlicht: March 17, 2016
In: Cell reports
Year: 2016, Jahrgang: 14, Heft: 12, Pages: 2962-2974
ISSN:2211-1247
DOI:10.1016/j.celrep.2016.02.068
Online-Zugang:Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1016/j.celrep.2016.02.068
Verlag, lizenzpflichtig, Volltext: http://www.sciencedirect.com/science/article/pii/S2211124716302030
Volltext
Verfasserangaben:Achuth Padmanabhan, Simone Anh-Thu Vuong, and Mark Hochstrasser
Beschreibung
Zusammenfassung:Targeted intracellular protein degradation in eukaryotes is largely mediated by the proteasome. Here, we report the formation of an alternative proteasome isoform in human cells, previously found only in budding yeast, that bears an altered subunit arrangement in the outer ring of the proteasome core particle. These proteasomes result from incorporation of an additional α4 (PSMA7) subunit in the position normally occupied by α3 (PSMA4). Assembly of “α4-α4” proteasomes depends on the relative cellular levels of α4 and α3 and on the proteasome assembly chaperone PAC3. The oncogenic tyrosine kinases ABL and ARG and the tumor suppressor BRCA1 regulate cellular α4 levels and formation of α4-α4 proteasomes. Cells primed to assemble α4-α4 proteasomes exhibit enhanced resistance to toxic metal ions. Taken together, our results establish the existence of an alternative mammalian proteasome isoform and suggest a potential role in enabling cells to adapt to environmental stresses.
Beschreibung:Gesehen am 23.10.2020
Beschreibung:Online Resource
ISSN:2211-1247
DOI:10.1016/j.celrep.2016.02.068