The tripartite motif family (TRIM) is a protein family.
Many TRIM proteins are induced by interferons, which are important component of resistance to pathogens and several TRIM proteins are known to be required for the restriction of infection by lentiviruses. TRIM proteins are involved in pathogen-recognition and by regulation of transcriptional pathways in host defence.
The tripartite motif is always present at the N-terminus of the TRIM proteins. The TRIM motif includes the following three domains:
(1) a RING finger domain(2) one or two B-box zinc finger domainswhen only one B-box is present, it is always a type-2 B-boxwhen two B-boxes are present the type-1 B-Box always precedes the type-2 B-Box(3) coiled coil regionThe C-terminus of TRIM proteins contain either:
Group 1 proteins: a C-terminal domain selected from the following list:NHL and IGFLMN domains, either in association or alonePHD domain associated with a bromodomainMATH domain (in e.g., TRIM37)ARF domain (in e.g., TRIM23)EXOIII domain (in e.g., TRIM19) orGroup 2 proteins: a SPRY C-terminal domaine.g. TRIM21The TRIM family is split into two groups that differ in domain structure and genomic organization:
Group 1 members possess a variety of C-terminal domains, and are represented in both vertebrate and invertebratesGroup 2 is absent in invertebrates, possess a C-terminal SPRY domainMembers of the family include:
Group 1PHD-BROMO domain containing: TRIM24 (TIF1α), TRIM28 (TIF1β), TRIM33 (TIF1γ)– act as corepressors1-10: TRIM1, TRIM2, TRIM3, TRIM8, TRIM911-20: TRIM12, TRIM13, TRIM14, TRIM16, TRIM18, TRIM1921-30: TRIM23, TRIM25, TRIM29, TRIM3031-40: TRIM32, TRIM36, TRIM3741-50: TRIM42, TRIM44, TRIM45, TRIM46, TRIM4751-60: TRIM51, TRIM53, TRIM54, TRIM55, TRIM56, TRIM57, TRIM5961-70: TRIM62, TRIM63, TRIM65, TRIM66, TRIM67, TRIM69, TRIM7071-75: TRIM71Group 21-10: TRIM4, TRIM5, TRIM6, TRIM7, TRIM1011-20: TRIM11, TRIM12, TRIM15, TRIM17, TRIM2021-30: TRIM21, TRIM22, TRIM26, TRIM27, TRIM3031-40: TRIM31, TRIM34, TRIM35, TRIM38, TRIM39, TRIM4041-50: TRIM41, TRIM43, TRIM48, TRIM49, TRIM5051-60: TRIM51, TRIM52, TRIM53, TRIM57, TRIM58, TRIM6061-70: TRIM61, TRIM64, TRIM68, TRIM69, TRIM7071-75: TRIM72, TRIM73, TRIM74, TRIM75