We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Are RNA Primers?

By E.A. Sanker
Updated Mar 03, 2024
Our promise to you
The Health Board is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At The Health Board, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Ribonucleic acid (RNA) primers play an essential role in deoxyribonucleic acid (DNA) replication, the copying of DNA molecules that occurs in all living organisms. Replication allows an organism to pass on genetic information, contained in a copy of its DNA, to its offspring. RNA primers help initiate replication on the molecular level. They act in conjunction with several enzymes, or proteins, that catalyze reactions involved in this process.

RNA, like DNA, is molecule consisting of subunits called nucleotides. Each nucleotide in an RNA or DNA chain contains a chemical compound known as a nucleobase. DNA nucleobases are adenine, thymine, guanine, and cytosine. In RNA, the compound uracil is used in place of thymine, but the other nucleobases are the same as in DNA.

Each nucleobase in an RNA or DNA strand chemically bonds with a complementary nucleobase on another DNA or RNA strand to form a base pair, creating a double helix. Adenine pairs with thymine or uracil, while guanine pairs with cytosine. The pattern of repeating units creates a sequence in which genetic information can be stored.

During replication, the enzyme helicase splits the bonds between nucleotides and separates the DNA molecule into its two constituent strands. Another enzyme, DNA polymerase, attaches complementary nucleotides to each single strand. This process creates a duplicate of the original DNA molecule by using each of the two complementary strands as a template.

DNA polymerase can add nucleotides to a developing strand, but it cannot create a new strand from scratch. This is where RNA primers come in. RNA primers are short strands of about 10 or 11 nucleotides each, and are formed by the enzyme primase. Primase binds to helicase to form a structure known as a primosome. The primosome attaches complementary nucleotides to the single stranded DNA molecule, creating an RNA primer, and the action of RNA primers along the chain sets off DNA polymerase.

The arrangement of atoms within nucleotide molecules causes DNA and RNA strands to have directionality — each strand has a specific orientation. Strand ends are named based on the area of the nucleotide molecule they terminate with. The five-prime (5’) end of a strand terminates with the fifth carbon atom in the molecule’s carbon ring structure. Complementary strands are oriented opposite one another, so the other strand would have a three-prime (3’) end at that location, terminating in its third carbon atom. To visualize this, if one strand of a double helix runs from 5’ to 3’ left to right, the opposite strand must run from 3’ to 5’ left to right.

DNA polymerase can only add nucleotides to the 3’ end, working towards the 5’ end. Only one RNA primer is needed to start this process from the leading strand, which ends in 3’. Replication of the opposite lagging strand is more complicated. DNA polymerase adds nucleotides backward along this strand intermittently, working in short sequences as the strands are split. Each sequence requires an RNA primer at its beginning, so several RNA primers are needed to replicate the lagging strand.

The Health Board is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

The Health Board, in your inbox

Our latest articles, guides, and more, delivered daily.

The Health Board, in your inbox

Our latest articles, guides, and more, delivered daily.