Why DNA polymerase 3 needs a primer to star replication.And whats happens when there is no AUG sequence on entire DNA.
You are confused among DNA replication, DNA transcrption, and RNA translation.
First, DNA replication happens during cell division, it create two exactly same daughter DNA.
Second, DNA transcription transcribes DNA sequence into RNA sequence, this RNA sequence may be used to synthesize protein, or RNA itself as signal, etc.
Third, RNA translation is the RNA sequence (codon) recognized by tRNA, and then synthesize protein sequence.
AUG is a codon in the RNA, the is recognized by tRNA, and then start translation. And please remember, DNA use A, G, C, T, but RNA use A, G, C, U, there is no U in DNA.
For DNA synthesis, why does it need primer? I have another answer for solving your question: https://biology.stackexchange.com/a/40954/17473