Differential Translation of Duck‐ and Rabbit‐Globin Messenger RNAs in Reticulocyte‐Lysate Systems

A 9 to 10‐S messenger RNA was purified from duck immature erythrocyte polyribosomes and found to direct the synthesis of several duck globin chains in a rabbit reticulocyte‐lysate protein‐synthesising system. The ability to compete with the endogenous rabbit globin mRNA was, however, very low. On the other hand, rabbit 9‐S RNA, when put into a duck immature erythrocyte‐lysate cell‐free system, was translated with high efficiency, effectively depressing the translation of the endogenous duck mRNA. These experiments lead us to conclude that between duck and rabbit messengers there are fundamental differences in the RNA structure at or near the initiation sites leading to their respective abilities to be recognised and translated with different efficiencies in cell‐free systems.