Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0409974 (lupus)
 22,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ascaris hemoglobin consists of eight subunits, each of which contains a C-terminal peptide with the sequence Glu-Glu-Lys-His repeated four times. When plotted on a beta-strand, this sequence leads to alternate lysines and glutamates on one side of the strand, and alternate glutamates and histidines on the other side, suggestive of a polar zipper which links the subunits together. A computer search of the protein database showed that the same or similar sequences also occur in other proteins. Some contain long repeats of Asp-Arg or Glu-Arg, among them the small nuclear ribonucleo-U1 70K protein which is an autoantigen in Systemic Lupus Erythematosis. These repeats appear to constitute the dominant epitopes in the autoimmune reaction. Single chains with Asp-Arg repeats may form alpha-helices in which alternate positively charged ridges and negatively charged grooves compensate each other. Several separate chains with Asp-Arg repeats could compensate each other's charges optimally by zipping together to beta-sheets. Several homeodomains of Drosophila as well as the human transcription factor SP1 contain repeats of glutamines. Molecular modelling, circular dichroism, electron and X-ray diffraction studies of a synthetic poly(L-glutamine) showed that it forms beta-sheets held together by hydrogen bonds between the main chain and side chain amides. Published data suggest that the function of these glutamine repeats consists in joining essential transcription factors bound to distant segments of DNA. The study of the structure and function of glutamine repeats has assumed medical importance with the discovery that Huntington's Disease and four other dominantly inherited diseases are associated with a lengthening of glutamine repeats in the proteins coded for by the affected genes.
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PMID:Polar zippers: their role in human disease. 765 65

Ascaris hemoglobin consists of 8 subunits, each of which contains a C-terminal peptide with the sequence Glu-Glu-Lys-His repeated 4 times. When plotted on a beta-strand, this sequence leads to alternate lysines and glutamates on one side of the strand, and alternate glutamates and histidines on the other side, suggestive of a polar zipper that links the subunits together. A computer search of the protein database showed that the same or similar sequences also occur in other proteins. Some contain long repeats of Asp-Arg or Glu-Arg, among them the small nuclear ribonucleo-U1 70K protein, which is an autoantigen in systemic lupus erythematosis. These repeats appear to constitute the dominant epitopes in the autoimmune reaction. Single chains with Asp-Arg repeats may form alpha-helices in which alternate positively charged ridges and negatively charged grooves compensate each other. Several separate chains with Asp-Arg repeats could compensate each other's charges optimally by zipping together to beta-sheets. Several homeodomains of Drosophila, as well as the human transcription factor SP1, contain repeats of glutamines. Molecular modeling, circular dichroism, and electron and X-ray diffraction studies of a synthetic poly(L-glutamine) showed that it forms beta-sheets held together by hydrogen bonds between the main-chain and side-chain amides. Published data suggest that the function of these glutamine repeats consists of joining essential transcription factors bound to distant segments of DNA.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Polar zippers: their role in human disease. 784 80

Cross-reactions of anti-human chorionic gonadotropin-beta (HCG-beta) antibody elicited by HCG-beta based antifertility vaccines with other autoantigens may occur due to identical or homologous protein subsequences. I have detected hitherto unreported identity of HCG-beta sequence with tetrapeptides of PECAM-1, galactosyl transferase-associated protein kinase, insulin receptor-related receptor and carboxypeptidase E. A predicted potential epitope of C-terminal peptide (CTP) of HCG-beta was identical to a tetrapeptide stretch of MCSF-1. The first 30 residue stretch of CTP was found to have yet unknown homologies of more than 56% with many auto-antigens including 60.1% with centromere protein C. The last 30 residue stretch of CTP was found for the first time to have 61.4-65.4% homology with subsequences of autoantigens SP-100, PM-SCL, D1 (64 kDa), lupus KU (p86), small nuclear ribonucleoprotein-associated proteins N, B and B', major centromere autoantigen B, centromere protein C, and dihydrolipoamide acetyl transferase component E2 of pyruvate, respectively.
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PMID:Predictions of Immunological Cross-Reactions of C-Terminal Peptide of Human Chorionic Gonadotropin beta-Chain Based Contraceptive Vaccine with Autoantigens. 1268 22