Abstract
The full sequence of the heavy chain of Immunoglobulin M (IgM) and a partial fragment of the recombination activating gene-1 (RAG-1) gene were sequenced in haddock, Melanogrammus aeglefinus, L. The complete transcript of haddock IgM consisted of 1865 bp and translated into a 572-aa peptide. The RAG-1 fragment was 1776 bp and was identified as the core region of RAG-1. These two immune genes were used in expression studies as markers of early development in haddock larvae. A DIG labelled oligoprobe of the RAG-1 gene was used in whole-mount in situ hybridisation (WISH). A hybridisation signal for RAG-1 was first detected in larvae at 25 days post-hatching (dph) in two bilateral symmetric regions of the head identified as the thymus. Further expression studies were carried out by RT-PCR analysis of RAG-1 and IgM on larval samples obtained during early development, i.e. from fertilisation to weaning. Haddock RAG-1 expression was detected after 21 days post-fertilisation (dpf) whilst IgM transcripts were not detected until 40 dpf, equivalent to day 29 post-hatching. These results suggest that the immune system in haddock starts to develop in larvae of 6-7 mm in length (25-29 dph). (c) 2006 Elsevier Ltd. All rights reserved.
Original language | English |
---|---|
Pages (from-to) | 71-85 |
Number of pages | 15 |
Journal | Fish & Shellfish Immunology |
Volume | 23 |
Issue number | 1 |
Early online date | 4 Oct 2006 |
DOIs | |
Publication status | Published - Jul 2007 |
Keywords
- haddock
- RAG-1
- IgM
- whole-mount in situ hybridisation
- gene expression
- cod gadus-morhua
- bass dicentrarchus-labrax
- carp cyprinus-carpio
- V(D)J recombination
- lymphoid organs
- larval haddock
- Atlantic cod
- rainbow-trout
- marine fish
- expression