Question

After the 43S complex binds to the 5' end of the mRNA, the complex then scans along the message until it reaches a recognizable nucleotide sequence. What is that sequence?

1) 5' - CCACCAUGC-3'
2) 3' - CCACCAUGC-5'

Answer 1

The recognizable nucleotide sequence that the 43S complex scans for after binding to the 5' end of the mRNA is the Kozak's consensus sequence. The consensus sequence around the AUG start codon in vertebrate genes is 5'-gccRccAUGG-3', where R can be either A or G, but not C or U. This sequence enhances the efficiency of translation.

Step-by-step explanation:

The recognizable nucleotide sequence that the 43S complex scans for after binding to the 5' end of the mRNA is the Kozak's consensus sequence. The Kozak's rules state that the consensus sequence around the AUG start codon in vertebrate genes is 5'-gccRccAUGG-3', where R can be either A or G, but not C or U. This sequence helps ensure the correct identification of the start codon and enhances the efficiency of translation.