Tcn2-flox Mouse

Tcn2, also known as transcobalamin-2, is an essential plasma protein crucial for the absorption, transportation, and cellular uptake of vitamin B12 [3]. It is involved in one-carbon metabolism pathways, which are vital for various biological processes such as DNA synthesis, methylation reactions, and cell proliferation [2].

In zebrafish, loss-of-function studies of tcn2 (the zebrafish ortholog of human Tcn2) showed that homozygous tcn2 -/- fish have reduced growth, and offspring of tcn2 -/- females exhibit gross developmental and metabolic defects, which can be rescued by vitamin B-12 supplementation, suggesting that Tcn2-mediated vitamin B-12 deposition in the yolk is necessary for early development [4]. In a mouse model relevant to multiple sclerosis, Tcn2 functions as a chaperone for FTY720, and the B12-Tcn2-CD320 pathway is essential for FTY720's mechanism of action in suppressing neuroinflammation [1].

In conclusion, Tcn2 is of great biological importance for vitamin B12-related processes. Studies using gene-knockout models in zebrafish and mice have revealed its roles in development and in diseases like multiple sclerosis, highlighting its potential as a therapeutic target in related conditions.