Gene expression profiling has shown that Ctnnal1 (catenin (cadherin associated protein; also called alpha catulin) is highly restricted in its expression to hematopoietic stem cells.
The alpha-catulinGFP allele was created by knocking a GFP marker into the first exon of the mouse Ctnnal1 gene (in frame with the start codon) to enable fluorescent detection of HSCs. This allele is expressed by only 0.02% of bone marrow hematopoietic cells, including almost all HSCs.
Although predicted to be a loss-of-function allele, both heterozygous and homozygous mice are born with expected Mendelian frequencies. Young adult homozygotes are normal in size, body mass, bone density and bone volume. Animals do not display any visible phenotype and are fertile. Heterozygotes and homozygotes exhibit normal hematopoiesis as well as normal hematopoietic stem cell frequency, hematopoietic stem cell cycle kinetics, and normal hematopoietic stem cell function upon primary and secondary transplantation into irradiated mice. They have the same lifespan as their wildtype littermates.
