The main purpose of this research is to study the role of thyroid status and vitamin B-12 on the regulation of folic acid function. This will be carried out by the following three approaches: 1. Study of the effect of thyroid hormones on folic acid polyglutamate and coenzyme distribution. 2. Investigation of effect of hypo and hyperthyroidism and folic acid binding proteins in liver and their role in folic acid regulation. 3. Study of distribution of folylpolyglutamate coenzymes between cytosol and mitochondria, with the view of identifying pools of folate which are specifically involved in formiminoglutamic acid metabolism.
