Upstream ORF-Encoded ASDURF Is a Novel Prefoldin-like Subunit of the PAQosome

  • J Proteome Res. 2020 Jan 3;19(1):18-27. doi: 10.1021/acs.jproteome.9b00599.
Philippe Cloutier  1 ,  Christian Poitras  1 ,  Denis Faubert  1 ,  Annie Bouchard  1 ,  Mathieu Blanchette  2 ,  Marie-Soleil Gauthier  1 ,  Benoit Coulombe  1  3
Affiliations
  • 1. Institut de Recherches Cliniques de Montréal , 110 Avenue des Pins Ouest , Montréal , Quebec H2W 1R7 , Canada.
  • 2. School of Computer Science , McGill University , 3480 University Street , Montréal , Quebec H3A 0E9 , Canada.
  • 3. Département de Biochimie et Médecine Moléculaire, Faculté de Médecine , Université de Montréal , 2900 Boulevard Édouart-Montpetit , Montréal , Quebec H3T 1J4 , Canada.
PMID: 31738558 DOI: 10.1021/acs.jproteome.9b00599
Abstract

The PAQosome is an 11-subunit chaperone involved in the biogenesis of several human protein complexes. We show that ASDURF, a recently discovered upstream open reading frame (uORF) in the 5' UTR of ASNSD1 mRNA, encodes the 12th subunit of the PAQosome. ASDURF displays significant structural homology to β-prefoldins and assembles with the five known subunits of the prefoldin-like module of the PAQosome to form a heterohexameric prefoldin-like complex. A model of the PAQosome prefoldin-like module is presented. The data presented here provide an example of a eukaryotic uORF-encoded polypeptide whose function is not limited to cis-acting translational regulation of downstream coding sequence and highlights the importance of including alternative ORF products in proteomic studies.

Keywords
AP-MS; ASDURF; BioID; PAQosome; R2TP/PFDL; chaperone; prefoldin; protein complex assembly; small ORF encoded peptide; uORF.