Practice question

Question

In anin vitrotranslation reaction, the 43S pre-initiation complex (PIC) was incubated with thein vitrotranscribed and capped mRNA forGene X, followed by addition of the 60S subunit. As a control, mRNA forGene Yisolated from cells was incubated in the same reaction. The mRNA for Gene Y was bound to the 80S ribosomes and polyribosomes, while mRNA of Gene X remained unbound. In a parallel experiment, mRNAs for both Gene X and Gene Y were found to be associatedin vivowith 80S and polyribosomes. The following statements were made to explain the above observation. A. Thein vitrosystem was globally defective for 80S assembly.B. Gene X mRNA has a sequence or structural feature that specifically prevents 80S assemblyin vitro.C. Gene X mRNA lacks a start codon.D. Gene X mRNA requires other cellular factors which are absent in thein vitromix to permit initiation.E. Thein vitroassay preferentially degrades Gene X mRNA. Which one of the following options represents all correct statements?