Protein-interacting Bro1-like domain of RhoA-binding protein Rhophilin and related domains
This family contains the Bro1-like domain of RhoA-binding proteins, Rhophilin-1 and -2, and related domains. 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), Brox, Bro1 and Rim20 (also known as PalA) from Saccharomyces cerevisiae, Ustilago maydis Rim23 (also known as PalC), and related domains. Rhophilin-1 and -2 bind both GDP- and GTP-bound RhoA. Bro1-like domains are boomerang-shaped, and part of the domain is a tetratricopeptide repeat (TPR)-like structure. In addition to this Bro1-like domain, Rhophilin-1 and -2, contain an N-terminal Rho-binding domain and a C-terminal PDZ (PS.D.-95, Disc-large, ZO-1) domain. Their PDZ domains have limited homology. Rhophilin-1 and -2 have different activities. The Drosophila knockout of Rhophilin-1 is embryonic lethal, suggesting an essential role in embryonic development. Roles of Rhophilin-2 may include limiting stress fiber formation or increasing the turnover of F-actin in the absence of high levels of RhoA signaling activity. The isolated Bro1-like domain of Rhophilin-1 binds human immunodeficiency virus type 1 (HIV-1) nucleocapsid. This family lacks the V-shaped (V) domain found in many members of the BRO1_Alix _like superfamily.
Jiyao W et al.(2023). "The conserved domain database in 2023.",