Protein-interacting V-domain of an uncharacterized family of the V_Alix_like superfamily
This domain family is comprised of uncharacterized plant proteins. It belongs to the V_Alix_like superfamily which includes the V-shaped (V) domains of Bro1 and Rim20 (also known as PalA) from Saccharomyces cerevisiae, mammalian Alix (apoptosis-linked gene-2 interacting protein X), (His-Domain) type N23 protein tyrosine phosphatase (HD-PTP, also known as PTPN23), and related domains. Alix, also known as apoptosis-linked gene-2 interacting protein 1 (AIP1), participates in membrane remodeling processes during the budding of enveloped viruses, vesicle budding inside late endosomal multivesicular bodies (MVBs), and the abscission reactions of mammalian cell division. It also functions in apoptosis. HD-PTP functions in cell migration and endosomal trafficking, Bro1 in endosomal trafficking, and Rim20 in the response to the external pH via the Rim101 pathway. Alix, HD-PTP, Bro1, and Rim20 all interact with the ESCRT (Endosomal Sorting Complexes Required for Transport) system. The mammalian Alix V-domain (belonging to a different family) contains a binding site, partially conserved in the superfamily, for the retroviral late assembly (L) domain YPXnL motif. The Alix V-domain is also a dimerization domain. In addition to this V-domain, members of the V_Alix_Rim20_Bro1_like superfamily also have an N-terminal Bro1-like domain, which binds components of the ESCRT-III complex. The Bro1-like domains of Alix and HD-PTP can also bind to human immunodeficiency virus type 1 (HIV-1) nucleocapsid. Many members of the V_Alix_like superfamily also have a proline-rich region (PRR).
Comment:based on the binding of Alix to the YPXnL (n=1-3) late domains of HIV and EIAV; late domains are short peptide motifs found in viral Gag proteins
Comment:some members of this superfamily have been shown to bind nonviral YPXnL motifs
Jiyao W et al.(2023). "The conserved domain database in 2023.",