Disease relevance of TRIM21

• Auto-antibodies to TRIM21 (Ro52) are a common serological feature of patients with Sjogren's syndrome and systemic lupus erythematosus (SLE) [1].
• By contrast, similar chimeras containing the components of TRIM21, a slightly more distant relative of TRIM5, did not restrict HIV-1 infection [2].
• A chimera consisting of monkey TRIM5alpha with a RING domain of human TRIM21 exhibited a half-life of 210 min, yet potently restricted human immunodeficiency virus; therefore, rapid turnover of TRIM5alpha is not required for its antiretroviral activity [3].
• The 52-kD SS-A/Ro protein is one of the antigenic targets strongly associated with the autoimmune response in mothers whose children have manifestations of neonatal lupus [4].
• Autoantibodies to Ro/SSA occur in nearly half of the patients with systemic lupus erythematosus and are associated with lymphopenia, photosensitive dermatitis, and pulmonary and renal disease, which suggests that they have an immunopathologic role [5].

Psychiatry related information on TRIM21

• The linguistic performance of 120 aphasic patients of the four standard syndromes assessed by the Aachen Aphasia Test (AAT) is analyzed by a nonmetric (ordinal) multidimensional scaling procedure (Smallest Space Analysis, SSA1) [6].

High impact information on TRIM21

• 52-kD SS-A/Ro: genomic structure and identification of an alternatively spliced transcript encoding a novel leucine zipper-minus autoantigen expressed in fetal and adult heart [4].
• In addition to the cDNA clone we previously reported for the full-length 52-kD SS-A/Ro protein, an interesting MOLT-4 cDNA clone, p52-2, was found to have an internal deletion of 231 nucleotides including the domain encoding the leucine zipper motif [4].
• In an attempt to analyze the regulated gene expression in lymphocytes by an HIV-suppressive immunomodulator, we have identified and cloned a novel gene encoding a 56-kDa protein, named SS-56, which is structurally related to the 52-kDa Ro/SSA antigen [7].
• Serum SS-A/Ro autoantibodies are commonly found in patients with Sjogren's syndrome, systemic lupus erythematosus, neonatal lupus, and subacute cutaneous lupus [8].
• Two cDNA clones encoding the 52-kD form of a protein present in human Ro/SSA ribonucleoprotein complexes were cloned from a lambda gt11 human thymocyte cDNA library [9].

Biological context of TRIM21

• The identity of cDNA was established by (a) the specificity of the antibody affinity purified from the recombinant protein, (b) the reactivity of the purified recombinant protein with prototype SS-A/Ro sera in immunoblot and ELISA, and (c) two-dimensional gel comigration of MOLT-4 cell 52-kD protein and the recombinant protein [8].
• We previously isolated and determined the nucleotide sequence of a cDNA clone that encodes the 52-kD form of the human Ro/SSA protein [5].
• The mapping of the human 52-kD Ro/SSA autoantigen gene to human chromosome 11, and its polymorphisms [5].
• Maternal antibody responses to the 52-kd SSA/RO p200 peptide and the development of fetal conduction defects [10].
• OBJECTIVE: To identify a finer level of antibody specificity for risk of congenital heart block (CHB) than reactivity to 52-kd SSA/Ro (Ro 52) [10].

Anatomical context of TRIM21

• In this study, we describe the role of Ro52 protein in T cell activation [11].
• These results indicate that expression of SSA/Ro antigen in human keratinocytes is modulated by SV40 infection and that this antigen is expressed to a greater degree in cells that are less differentiated, transformed, or proliferating [12].
• La/SS-B and/or 52 kDa Ro antigen(s) were found to be present in the cytoplasm of the B lymphoblastoid cells at a higher base level in EBV-infected cell lines than in the EBV-negative cell lines [13].
• Patients with several different connective tissue diseases including Sjögren's syndrome and systemic lupus erythematosus produce autoantibodies reacting with a 52kD protein component of the Ro/SS-A antigen [14].
• The results showed that keratinocytes receiving UVB irradiation expressed Ro/SSA antigen on cell membranes in a dose-dependent fashion [15].

Associations of TRIM21 with chemical compounds

• Effective separation of the 52 kDa SSA/Ro polypeptide from the 48 kDa SSB/La polypeptide by altering conditions of polyacrylamide gel electrophoresis [16].
• 17beta-estradiol treatment also induced Ro/SSA antigen expression dose-dependently [15].
• The reaction to SSA but not to MAM suggested the presence of sialic acid linked alpha2,6 to galactose in both cellular and serum TNX [17].

Physical interactions of TRIM21

• These purified antibodies binding the 197-207 peptide from 52 kDa Ro (anti-52LZ) bound native 60 kDa Ro as well as denatured 52 kDa Ro [18].

Other interactions of TRIM21

• These data indicate that autoantibody responses to the 60-kDa Ro Ag can preferentially target discontinuous epitopes and that the ability to recognize continuous epitopes is accompanied by the appearance of 52-kDa Ro autoantibodies [19].
• Antibodies were affinity purified from a peptide within the leucine zipper region of 52 kDa Ro [18].
• Our data reveal a novel function of Ro52 in CD28-mediated pathway, which eventually contributes to cytokine production and expression of the T cell biological programs [11].
• The region contains the complete SSA/Ro52 and RRM1 genes, exons 7-12 of the GOK gene, and the psirad pseudo-gene [20].
• Contrary to the data published by other authors, our results indicate that calreticulin is not a Ro/SS-A autoantigen [21].

Analytical, diagnostic and therapeutic context of TRIM21

• In fact, peptides from 60 kDa Ro have a molecular interaction with the 52 kDa Ro peptide as well as full-length 52 kDa Ro when assessed by surface plasmon resonance [18].
• To measure serum antibody levels, ELISA using purified recombinant TRIM21 protein was developed [22].
• The presence of s-TRIM21-Abs was confirmed by Western blotting using bacterially expressed TRIM21 gene product and was evaluated for clinicopathological significance in patients with esophageal SCC. s-TRIM21-Abs were detected in 18 (20%) of 91 patients with esophageal SCC but not in 42 healthy donors [22].
• Immunoprecipitation of in vitro-translated 35S-labeled 52 beta form was performed to evaluate the antigenicity of this novel form of 52-kD SS-A/Ro [4].
• The locations of SSA/Ro, U1RNP, and DNA antigens were studied by indirect immunofluorescence using monospecific antibodies [12].

References