PRY/SPRY domain in tripartite motif-binding protein 5 (TRIM5), also known as RING finger protein 88 (RNF88)
This domain, consisting of the distinct N-terminal PRY subdomain followed by the SPRY subdomain, is found at the C-terminus of TRIM5 which is also known as RING finger protein 88 (RNF88) or TRIM5alpha (TRIM5a), an antiretroviral restriction factor and a retrovirus capsid sensor in immune signaling. TRIM5 domain is composed of RING/B-box/coiled-coil core and also known as RBCC protein. It blocks retrovirus infection soon after the virion core enters the cell cytoplasm by recognizing the capsid protein lattice that encases the viral genomic RNA; the SPRY domain provides the capsid recognition motif that dictates specificity to retroviral restriction. TRIM5a, an E3 ubiquitin ligase, promotes innate immune signaling by activating the TAK1 kinase complex by cooperating with the heterodimeric E2, UBC13/UEV1A. It also stimulates NFkB and AP-1 signaling, and the transcription of inflammatory cytokines and chemokines, and amplifies these activities upon retroviral infection. Interaction of its PRY-SPRY or cyclophilin domains with the retroviral capsid lattice stimulates the formation of a complementary lattice by TRIM5, with greatly increased TRIM5 E3 activity, and host cell signal transduction.
Jiyao W et al.(2023). "The conserved domain database in 2023.",