Characterization and expression of the transcription factor PU.1 during LPS-induced inflammation in the rainbow trout (Oncorhynchus mykiss).

Abstract

The transcription factor PU.1 plays a key role in hematopoietic lineage development and therefore in determining immune cell fate. A full length cDNA transcript of 1237 nucleotides encoding a highly conserved putative protein of 293 amino acids was identified by EST analysis in lipopolysaccharide (LPS) activated trout macrophages. Phylogenetic analyses highlight the significant level of structural conservation of the PU.1 transcription factor reinforcing the importance of this molecule in animal immunity. In trout, the PU.1 mRNA shows a tissue-specific expression pattern and is induced in vivo by LPS in muscle, liver, intestine and brain. Furthermore PU.1 is highly expressed in trout macrophages in primary culture. In situ expression analysis in the head kidney describes a large number of PU.1+ve cells distributed through the tissue in both LPS-treated and control animals. Cellular proliferation examined by BrdU immunohistochemistry (IHC) shows that LPS regulates hematopoietic processes in adult fish by stimulating cellular proliferation 3 days after treatment. These studies provide initial insights into hematopoietic/cellular processes in the head kidney of rainbow trout after in vivo LPS challenge.

• Authors: Laia Ribas, Nerea Roher, Milagros Martínez, Joan Carles Balasch, Carmen Doñate, Frederick W Goetz, Dimitar Iliev, Josep V Planas, Lluis Tort, Simon Mackenzie
• Journal: Fish & shellfish immunology (Fish Shellfish Immunol) Vol. 24 Issue 1 Pg. 35-45 (Jan 2008) ISSN: 1050-4648 [Print] England
• PMID: 18083598 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Lipopolysaccharides
• Proto-Oncogene Proteins
• Trans-Activators
• proto-oncogene protein Spi-1

Topics

• Amino Acid Sequence
• Animals
• Base Sequence
• Gene Expression Profiling
• Gene Expression Regulation (drug effects)
• In Situ Hybridization
• Inflammation (chemically induced, genetics)
• Lipopolysaccharides (pharmacology)
• Molecular Sequence Data
• Oncorhynchus mykiss (genetics)
• Phylogeny
• Proto-Oncogene Proteins (chemistry, genetics)
• Sequence Alignment
• Sequence Homology, Amino Acid
• Trans-Activators (chemistry, genetics)