Activation of beta-catenin in the stem cell region of crypts during growth of the small intestine in infant rats.
The Wnt/beta-catenin pathway has been proposed as promoting intestinal stem cell division. Wnt ligands activate cytoplasmic beta-catenin and increase nuclear translocation of beta-catenin that binds to the Tcf-4 transcription factor. The aim of this study was to investigate beta-catenin expression in the stem cell region of crypts during intestinal growth in rats. Litters of DAxPVG/c rats were humanely killed at 7, 14, 21, 35, and 72 days of life. beta-Catenin and Tcf-4 were quantified by immunoperoxidase staining and image analysis with cumulative signal analysis. Cytoplasmic and nuclear expression of beta-catenin peaked nearly 2-fold at day 14 (versus day 7) of life in the stem cell region of intestinal crypts. Tcf-4 nuclear expression peaked earlier at 7 days and was lower thereafter with age. We conclude that the Wnt/beta-catenin pathway is activated in the stem cell region of intestinal crypts during growth of the small intestine.
Camac
Kimberley S
KS
Department of Gastroenterology and Hepatology, The Queen Elizabeth Hospital, Woodville South, Australia.
Thompson
Fiona M
FM
Cummins
Adrian G
AG
D000375:Aging / Q000378:metabolism; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D007421:Intestine, Small / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D051381:Rats; D015398:Signal Transduction; D013234:Stem Cells / Q000378:metabolism*; D013997:Time Factors; D000073940:Transcription Factor 4; D014157:Transcription Factors / Q000378:metabolism; D051153:Wnt Proteins / Q000378:metabolism; D051176:beta Catenin / Q000378:metabolism*
C495268:Ctnnb1 protein, rat; D004268:DNA-Binding Proteins; C491192:Tcf4 protein, rat; D000073940:Transcription Factor 4; D014157:Transcription Factors; D051153:Wnt Proteins; D051176:beta Catenin