Transcobalamin II synthesized in the intestinal villi facilitates transfer of cobalamin to the portal blood

Research was conducted to determine the cellular component of the intestinal villus where transcobalamin II (TCII) is synthesized since the protein provides an important function in the intestinal absorption of vitamin B12. The TCII transcript was identified by the northern blot analysis of RNA from both proximal and distal small intestine. Results indicate that TCII is constitutively expressed in the intestinal villi where vascular endothelium is abundant.