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the nucleotide sequence encoding four amino acids near the amino terminus of a 10-kd protein is 5™-ACT GAT TGC GTT-3™. This sequence is mutated by insertion of a single nucleotide (A) in the second codon and becomes 5™-ACT GAA TTG CGT-3™. Which consequences of this mutation is most likely?

a. altered cell-cycle checkpoint
b. decreased rate of transcription
c. protein truncation
d. single amino acid substitution

d ?

ddddddd

ddddddddddddddd

sorry guys, i think it is ccccccc, because the insertion can lead to frame shift, so a stop coden may appear earlier than normal resulting in a truncated protien

c or d? I am confused

bbbbbbb

I would go with C.

insertion of single AA would caused early stopping of transcription

yes would go with C insertion of single aa causes early stop codon and therefore protein truncation.

could be DDD