Figure 10.

EM micrographs of double-row polysomes formed during 2 h of translation in the cell-free systems programmed with different luciferase mRNA constructs. (a, b) mRNAs with both 5′ and 3′ UTRs: 5′UTR_Obelin-Luc-3′UTR_TMV, and 5′UTR_TMV-Luc-3′UTR_TMV, respectively; (c, d) mRNAs with only 5′UTR: 5′UTR_Obelin-Luc, and 5′UTR_TMV-Luc (Ω-Luc), respectively; (e) mRNA with only 3′UTR: Luc-3′UTR_TMV; (f) mRNA without specific 5′ and 3′ UTRs (Luc). Specimens were prepared by surface spreading and negatively stained with uranyl acetate.