The membrane associated accessory protein is an adeno-associated viral egress factor.

Journal Article (Journal Article)

Adeno-associated viruses (AAV) rely on helper viruses to transition from latency to lytic infection. Some AAV serotypes are secreted in a pre-lytic manner as free or extracellular vesicle (EV)-associated particles, although mechanisms underlying such are unknown. Here, we discover that the membrane-associated accessory protein (MAAP), expressed from a frameshifted open reading frame in the AAV cap gene, is a novel viral egress factor. MAAP contains a highly conserved, cationic amphipathic domain critical for AAV secretion. Wild type or recombinant AAV with a mutated MAAP start site (MAAPΔ) show markedly attenuated secretion and correspondingly, increased intracellular retention. Trans-complementation with MAAP restored secretion of multiple AAV/MAAPΔ serotypes. Further, multiple processing and analytical methods corroborate that one plausible mechanism by which MAAP promotes viral egress is through AAV/EV association. In addition to characterizing a novel viral egress factor, we highlight a prospective engineering platform to modulate secretion of AAV vectors or other EV-associated cargo.

Full Text

Duke Authors

Cited Authors

  • Elmore, ZC; Patrick Havlik, L; Oh, DK; Anderson, L; Daaboul, G; Devlin, GW; Vincent, HA; Asokan, A

Published Date

  • October 29, 2021

Published In

Volume / Issue

  • 12 / 1

Start / End Page

  • 6239 -

PubMed ID

  • 34716331

Pubmed Central ID

  • PMC8556243

Electronic International Standard Serial Number (EISSN)

  • 2041-1723

Digital Object Identifier (DOI)

  • 10.1038/s41467-021-26485-4


  • eng

Conference Location

  • England