Protein-interacting, N-terminal, Bro1-like domain of Saccharomyces cerevisiae Bro1 and related proteins
This family contains the N-terminal, Bro1-like domain of Saccharomyces cerevisiae Bro1 and related proteins. It belongs to the BRO1_Alix_like superfamily which also includes the Bro1-like domains of mammalian Alix (apoptosis-linked gene-2 interacting protein X), His-Domain type N23 protein tyrosine phosphatase (HD-PTP, also known as PTPN23), RhoA-binding proteins Rhophilin-1 and -2, Brox, Saccharomyces cerevisiae Rim20 (also known as PalA), Ustilago maydis Rim23 (also known as PalC), and related domains. Alix, HD-PTP, Brox, Bro1, Rim20, and Rim23, interact with the ESCRT (Endosomal Sorting Complexes Required for Transport) system. Bro1 participates in endosomal trafficking. Bro1-like domains are boomerang-shaped, and part of the domain is a tetratricopeptide repeat (TPR)-like structure. Bro1-like domains bind components of the ESCRT-III complex: Snf7 in the case of Bro1. Snf7 binds to a conserved hydrophobic patch on the middle of the concave side of the Bro1 domain. RIM20, and some other members of the BRO1_Alix_like superfamily including Alix, also have a V-shaped (V) domain. In the case of Alix, the V-domain contains a binding site for the retroviral late assembly (L) domain YPXnL motif, which is partially conserved in the superfamily. The Alix V-domain is also a dimerization domain. The C-terminal portion (V-domain and proline rich-region) of Bro1 interacts with Doa4, a protease that deubiquitinates integral membrane proteins sorted into the lumenal vesicles of late-endosomal multivesicular bodies. It interacts with a YPxL motif in the Doa4 catalytic domain to stimulate its deubiquitination activity.
Jiyao W et al.(2023). "The conserved domain database in 2023.",