RAG1/2 re-expression causes receptor revision in a model B cell line
Tanya R Da Sylva1, Ivan C Fong, Lesley A Cunningham
1Faculty of Pure and Applied Science, York University, Room 136, Farquharson Building, 4700 Keele St., Toronto, Ont., Canada M3J 1P3. dasylva@yorku.ca
Molecular Immunology
|May 17, 2006
Summary
Mature B cells can re-express RAG1 and RAG2, leading to immunoglobulin receptor revision and altered gene expression. This finding is crucial for understanding immune disorders and autoimmune states.
Area of Science:
- Immunology
- Molecular Biology
- Genetics
Background:
- Recombination-activating genes (RAG1/2) are critical for V(D)J recombination in developing B cells.
- Mature B cells typically suppress RAG1/2 expression, but re-expression in the periphery is linked to autoimmunity.
Purpose of the Study:
- To investigate the molecular consequences of RAG1/2 expression in mature lymphocytes.
- To understand the role of RAG1/2 re-expression in immune disorders.
Main Methods:
- Utilized M12 (RAG-) and DR3 (RAG1+/RAG2+) mouse B cell lines.
- Analyzed gene expression profiles using microarray and RT-PCR.
Main Results:
- RAG1/2 expression induced receptor revision in DR3 cells, including Igkappa deletion and Iglambda rearrangement.
- Significant differences in gene expression (fibronectin, lysyl oxidase, TAP2, B220, Igkappa, TIS11B, HMG2, DNAPKcs) were observed between M12 and DR3 lines.
Conclusions:
- RAG1/2 re-expression in mature lymphocytes triggers receptor revision and alters the cellular gene expression profile.
- This model provides insights into the molecular mechanisms underlying RAG re-expression and its potential link to immune dysregulation.
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