The tripartite motif family (TRIM) is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

family.

Function

Many TRIM proteins are induced by

interferon Interferons (IFNs, ) are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten the ...

s, which are important component of resistance to pathogens and several TRIM proteins are known to be required for the restriction of infection by

lentivirus ''Lentivirus'' is a genus of retroviruses that cause chronic and deadly diseases characterized by long incubation periods, in humans and other mammalian species. The genus includes the human immunodeficiency virus (HIV), which causes AIDS. Lent ...

es. TRIM proteins are involved in pathogen-recognition and by regulation of transcriptional pathways in host defence.

Structure

The tripartite motif is always present at the

N-terminus The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the ami ...

of the TRIM proteins. The TRIM motif includes the following three domains: * (1) a

RING finger The ring finger, third finger, fourth finger, leech finger, or annulary is the fourth digit of the human hand, located between the middle finger and the little finger. Sometimes the term ring finger only refers to the fourth digit of a left-han ...

domain * (2) one or two

B-box zinc finger In molecular biology the B-box-type zinc finger domain is a short protein domain of around 40 amino acid residues in length. B-box zinc fingers can be divided into two groups, where types 1 and 2 B-box domains differ in their consensus sequence ...

domains ** when only one B-box is present, it is always a type-2 B-box ** when two B-boxes are present the type-1 B-Box always precedes the type-2 B-Box * (3)

coiled coil A coiled coil is a structural motif in proteins in which 2–7 alpha-helices are coiled together like the strands of a rope. (Dimers and trimers are the most common types.) Many coiled coil-type proteins are involved in important biological fun ...

region The

C-terminus The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is ...

of TRIM proteins contain either: * Group 1 proteins: a C-terminal domain selected from the following list: **

NHL The National Hockey League (NHL; french: Ligue nationale de hockey—LNH, ) is a professional ice hockey league in North America comprising 32 teams—25 in the United States and 7 in Canada. It is considered to be the top ranked professional ...

and IGFLMN domains, either in association or alone ** PHD domain associated with a

bromodomain A bromodomain is an approximately 110 amino acid protein domain that recognizes acetylated lysine residues, such as those on the ''N''-terminal tails of histones. Bromodomains, as the "readers" of lysine acetylation, are responsible in transducin ...

** MATH domain (in e.g., TRIM37) ** ARF domain (in e.g., TRIM23) ** EXOIII domain (in e.g., TRIM19) or * Group 2 proteins: a SPRY C-terminal domain **e.g. TRIM21

Family members

The TRIM family is split into two groups that differ in domain structure and genomic organization: * Group 1 members possess a variety of

C-terminal The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is ...

domains, and are represented in both vertebrate and invertebrates * Group 2 is absent in invertebrates, possess a C-terminal SPRY domain Members of the family include: * Group 1 ** PHD-BROMO domain containing:

TRIM24 Tripartite motif-containing 24 (TRIM24) also known as transcriptional intermediary factor 1α (TIF1α) is a protein that, in humans, is encoded by the ''TRIM24'' gene. Function The protein encoded by this gene mediates transcriptional control b ...

(TIF1α),

TRIM28 Tripartite motif-containing 28 (TRIM28), also known as transcriptional intermediary factor 1β (TIF1β) and KAP1 (KRAB-associated protein-1), is a protein that in humans is encoded by the ''TRIM28'' gene. Function The protein encoded by this ge ...

(TIF1β),

TRIM33 E3 ubiquitin-protein ligase TRIM33, also known as (ectodermin homolog and tripartite motif-containing 33) is a protein encoded in the human by the gene ''TRIM33'', a member of the tripartite motif family. TRIM33 is thought to be a transcriptional ...

(TIF1γ)– act as

corepressor In the field of molecular biology, a corepressor is a molecule that represses the expression of genes. In prokaryotes, corepressors are small molecules whereas in eukaryotes, corepressors are proteins. A corepressor does not directly bind to DNA, b ...

s ** 1-10: TRIM1,

TRIM2 Trim or TRIM may refer to: Cutting * Cutting or wiktionary:trim#English, trimming small pieces off something to remove them ** Book trimming, a stage of the publishing process ** Pruning, trimming as a form of pruning often used on trees Decora ...

TRIM3 Tripartite motif-containing protein 3 is a protein that in humans is encoded by the ''TRIM3'' gene. The protein encoded by this gene is a member of the tripartite motif (TRIM) family, also called the 'RING-B-box-coiled-coil' (RBCC) subgroup of RIN ...

, TRIM8,

TRIM9 Tripartite motif-containing protein 9 is a protein that in humans is encoded by the ''TRIM9'' gene. The protein encoded by this gene is a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a ...

** 11-20: TRIM12, TRIM13, TRIM14, TRIM16, TRIM18, TRIM19 ** 21-30: TRIM23,

TRIM25 Tripartite motif-containing protein 25 is a protein that in humans is encoded by the ''TRIM25'' gene. Function The protein encoded by this gene is a member of the tripartite motif (TRIM) family grouping more than 70 TRIMs. TRIM proteins primari ...

, TRIM29, TRIM30 ** 31-40:

TRIM32 Tripartite motif-containing protein 32 is a protein that in humans is encoded by the ''TRIM32'' gene. Since its discovery in 1995, TRIM32 has been shown to be implicated in a number of diverse biological pathways. Structure The protein encoded ...

, TRIM36, TRIM37 ** 41-50: TRIM42, TRIM44, TRIM45, TRIM46, TRIM47 ** 51-60: TRIM51, TRIM53, TRIM54, TRIM55, TRIM56, TRIM57, TRIM59 ** 61-70: TRIM62,

TRIM63 E3 ubiquitin-protein ligase TRIM63, also known as "MuRF1" (Muscle Ring-Finger Protein-1), is an enzyme that in humans is encoded by the ''TRIM63'' gene. This gene encodes a member of the RING zinc finger protein family found in striated muscle a ...

, TRIM65, TRIM66, TRIM67,

TRIM69 Tripartite motif containing 69 is a protein that in humans is encoded by the TRIM69 gene. Function This gene encodes a member of the RING-B-box-coiled-coil (RBCC) family and encodes a protein with an N-terminal RING finger motif, a PRY domain ...

, TRIM70 ** 71-75: TRIM71 * Group 2 ** 1-10: TRIM4,

TRIM5 Tripartite motif-containing protein 5 also known as RING finger protein 88 is a protein that in humans is encoded by the ''TRIM5'' gene. The alpha isoform of this protein, TRIM5α, is a retrovirus restriction factor, which mediates a species-specif ...

, TRIM6, TRIM7, TRIM10 ** 11-20: TRIM11, TRIM12, TRIM15, TRIM17, TRIM20 ** 21-30:

TRIM21 Tripartite motif-containing protein 21, also known as E3 ubiquitin-protein ligase TRIM21, is a protein that in humans is encoded by the ''TRIM21'' gene. Alternatively spliced transcript variants for this gene have been described but the full-length ...

TRIM22 Tripartite motif-containing 22, also known as TRIM22, is a protein which in humans is encoded by the ''TRIM22'' gene. Function The protein encoded by this gene is a member of the tripartite motif (TRIM) family. The TRIM motif includes three z ...

, TRIM26, TRIM27, TRIM30 ** 31-40: TRIM31, TRIM34, TRIM35, TRIM38, TRIM39, TRIM40 ** 41-50: TRIM41, TRIM43, TRIM48, TRIM49, TRIM50 ** 51-60: TRIM51, TRIM52, TRIM53, TRIM57, TRIM58, TRIM60 ** 61-70: TRIM61, TRIM64, TRIM68,

, TRIM70 ** 71-75: TRIM72, TRIM73, TRIM74, TRIM75

References

Gene expression Transcription coregulators {{protein-stub