Influence of maternal dietary zinc intake on in vitro tubulin polymerization in fetal rat brain

The hypothesis that one of the biochemical lesions underlying zinc deficiency-induced teratogenicity is altered microtubule formation was tested. Day 19 fetuses from zinc-deficient Sprague-Dawley dams were characterized by low brain supernate zinc concentrations and slow brain tubulin polymerization rates compared to controls. Brain supernate tubulin and protein concentrations were similar in zinc-deficient and control fetuses. In vitro brain tubulin polymerization rates were increased following addition of zinc to either control or zinc-deficient brain supernates; however, the stimulatory effect of added zinc on polymerization was significantly higher in brain supernates obtained from zinc-deficient fetuses compared to controls. These results support the idea that one effect of fetal zinc deficiency is a reduction in tubulin polymerization, which in turn may result in altered microtubule function.