

Other version: http://www.jimmunol.org/cgi/reprint/165/6/2987.pdf
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Dysregulated expression of the Cd22 gene as a result of a short interspersed nucleotide element insertion in Cd22a lupus-prone mice |
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Authors | ![]() | |
Published in | The Journal of immunology. 2000, vol. 165, no. 6, p. 2987-2996 | |
Abstract | The Cd22 gene encodes a B cell-specific adhesion molecule that modulates B cell Ag receptor-mediated signal transduction, and is allelic to a lupus-susceptibility locus in New Zealand White (NZW) mice. In this study, we show that, in addition to the wild-type transcripts, NZW (Cd22a) mice synthesize aberrant CD22 mRNAs that contain approximately 20-120 nucleotide insertions upstream of the coding region between exons 2 and 3, and/or approximately 100-190 nucleotide deletions of exon 4. Sequence analysis revealed that these aberrant mRNA species arose by alternative splicing due to the presence in the NZW strain of a 794-bp sequence insertion in the second intron, containing a cluster of short interspersed nucleotide elements. Both the presence of sequence insertion and aberrantly spliced mRNAs were specific to mice bearing the Cd22a and Cd22c alleles. Up-regulation of CD22 expression after LPS activation appeared impaired in Cd22a spleen cells (twice lower than in Cd22b B cells). Furthermore, we show that partial CD22 deficiency, i.e., heterozygous level of CD22 expression, markedly promotes the production of IgG anti-DNA autoantibodies in C57BL/6 (Cd22b) mice bearing the Y chromosome-linked autoimmune acceleration gene, Yaa. Taken together, these results suggest that a lower up-regulation of CD22 on activated B cells (resulting from Cd22 gene anomaly in Cd22a mice or from CD22 heterozygosity in mutants obtained by gene targeting) is implicated in autoantibody production, providing support for Cd22a as a possible candidate allele contributing to lupus susceptibility. | |
Keywords | Alternative Splicing/immunology — Animals — Antigens, CD/biosynthesis/ genetics — Antigens, CD22 — Antigens, Differentiation, B-Lymphocyte/biosynthesis/ genetics — B-Lymphocytes/immunology/metabolism — Base Sequence — Cell Adhesion Molecules — Exons — Gene Expression Regulation/ immunology — Immunologic Deficiency Syndromes/genetics — Introns — Lectins — Lipopolysaccharides/immunology — Lupus Nephritis/ genetics/ immunology — Lymphocyte Activation/genetics — Male — Mice — Mice, Inbred AKR — Mice, Inbred C3H — Mice, Inbred C57BL — Mice, Inbred CBA — Mice, Inbred DBA — Mice, Inbred MRL lpr — Mice, Inbred NZB — Mice, Mutant Strains — Molecular Sequence Data — Mutagenesis, Insertional/ immunology — RNA Precursors/genetics/metabolism — RNA, Messenger/biosynthesis — Sequence Deletion — Short Interspersed Nucleotide Elements/ immunology — Spleen/cytology — Up-Regulation/immunology — Y Chromosome/immunology | |
Identifiers | PMID: 10975807 | |
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Citation (ISO format) | MARY, Charles et al. Dysregulated expression of the Cd22 gene as a result of a short interspersed nucleotide element insertion in Cd22a lupus-prone mice. In: The Journal of immunology, 2000, vol. 165, n° 6, p. 2987-2996. doi: 10.4049/jimmunol.165.6.2987 https://archive-ouverte.unige.ch/unige:11445 |