Fig. 3.

EMSA using the Zip5 3′-UTR stem-loop RNA and soluble or polysomal ribonucleoprotein fractions from visceral yolk sac or XEN cells. A uniformly labeled Zip5 3′-UTR sequence, corresponding to nucleotides 22 through 84 of the Zip5 3′-UTR (mouse; Fig. 1), was incubated with or without either the soluble (S) or the polysomal (P) RNP fraction isolated from embryonic VYS or XEN cells. VYS were harvested on day 14 from pregnant dams fed a zinc adequate (ZnA; A) or zinc deficient (ZnD; D) diet beginning on day 8 of pregnancy. XEN cells were cultured in ZnA (A) or ZnD (D) media for 48 h. Where indicated, a 100-fold molar excess of unlabeled competitor (cold) was included in the reaction. Reaction products were size fractionated and visualized by autoradiography