B cells develop in the zebrafish pancreas.
The zebrafish, with its transparent free-living embryo, is a useful organism for investigating early stages in lymphopoiesis. Previously, we showed that T cells differentiate in the thymus by day 4, but no sites for B cell differentiation were seen until 3 weeks. We report here that on day 4, we detect rearrangements of genes encoding B cell receptors in DNA extracted from whole fish. Also by day 4, rag1 transcripts are seen in the pancreas, an organ not previously associated with lymphopoiesis; by day 10, Igmu transcripts are detected here. Thus, in zebrafish, the pancreas assumes the role of both the liver in fetal mice and the spleen in neonatal mice.
Danilova
Nadia
N
Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
Steiner
Lisa A
LA
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D004247:DNA / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D015322:Gene Rearrangement, B-Lymphocyte; D016654:Genes, RAG-1; D007148:Immunoglobulin mu-Chains / Q000235:genetics; D017403:In Situ Hybridization; D038041:Lymphopoiesis / Q000235:genetics / Q000276:immunology; D051379:Mice; D010179:Pancreas / Q000196:embryology* / Q000254:growth & development / Q000276:immunology*; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics / Q000254:growth & development / Q000276:immunology*
D007148:Immunoglobulin mu-Chains; D004247:DNA