What is the difference between promoter and primer

A promoter is a region of DNA which comes before upstream of the transcriptional start site. Promoters 'promote' the transcription of the gene they lie upstream of. When specific transcription factors bind to the promoter, RNA polymerase is activated to transcribe the gene. They are short, single stranded nucleic acid molecules. DNA polymerases are only able to start adding nucleotides to the 3' end of an existing nucleotide. They cannot bind to a single stranded template and start synthesising the complementary strand from scratch.

They require a primer an RNA primer in this case , bound to the template, to begin synthesising a complementary strand. What's the difference between a promoter, a primer and a probe? Answered by Esther G. Need help with Biology? There are three types of promoter elements as core promoter, proximal promoter and distal promoter. The core promoter is the minimal portion of the promoter required to initiate transcription.

It is located most proximal to the start codon. TATA box is a conserved region found in many eukaryotic core promoters. It is found 25 to 35 base pairs upstream of the transcription start site. The proximal promoter is found more upstream to the core promoter.

Generally, it is located base pairs upstream to the start codon and contains primary regulatory elements. The distal promoter is found upstream to the proximal promoter, and it contains additional regulatory elements. Bacterial promoters have two short sequence elements in their promoters.

They are known as element and element. Primer is a short nucleotide sequence designed for the amplification of target DNA. In contrast, the promoter is a specific regulatory DNA sequence found upstream to the transcription initiation site of a gene. So, this is the key difference between primer and promoter. Primers are about 20 base pairs long while promoter can have base pairs.

Functionally, primers are served as starting sequences for the new strand synthesis while promoters control gene transcription by providing binding sites for RNA polymerase and other transcription factors. Moreover, a promoter is defined as the direction of the transcription and indicates the sense strand of a gene. The below info-graphic tabulates more comparisons related to the difference between primer and promoter.

Primers are short nucleotide sequences complementary to the flanking ends of the target DNA double-strand. Two types of primers are used in PCR. They serve as the starting sequences for the synthesis of new strands.

Primers are commercially designed, and they are temperature stable sequences. On the other hand, the promoter is a regulatory sequence of a gene located upstream to the transcription initiation site. Promoters control the transcription of genes.

They provide binding sites for RNA polymerase and transcription factors to initiate transcription. Thus, this is the summary of the difference between primer and promoter. Org, , Available here. WikiJournal of Medicine 4 1. Samanthi Udayangani holds a B.