Difference Between Sense and Antisense Strand

Key Difference – Sense vs Antisense Strand

DNA molecules possess all the genetic information, which is necessary for the growth and maintenance of an organism.DNAis the primary heredity unit of most of the organisms. DNA is a complex molecule that composed of four nucleotides, namely;adenine (A), guanine (G), cytosine (C), andthymine(T). The sequences of these bases determine the instructions in the genome. DNA molecule has two strands. Along with the phosphate group and deoxyribose sugar group (collectively called the backbone of DNA), double-stranded DNA molecule forms its unique shape; a double helix. The shape is formed by coiling these two antiparallel strands, one from 5’ to 3’ and the other from 3’ to 5’. Two strands are held together by hydrogen bonds. These two strands are named based on how it serves during the transcription process. Transcription is the first step of protein production, where information in a particular DNA segment is copied into a newmRNA(messenger-RNA) molecule with the presence ofRNApolymerase enzyme. During thetranscription, one DNA strand actively participates as a template, which is called antisense strand or template strand. The other complementary strand is called sense strand or coding strand. Thekey differenceis thatunlike antisense strand, the sense strand is not used in the transcription process. In this article, the difference between sense and antisense strands of DNA is discussed.

What is Sense Strand?

Sense strand is the strand of DNA that is not used as a template in the process of transcription. But the resulting RNA molecule is exactly identical to the sense strand, except for the presence of Uracil (U) instead of thymine (T). Sense strand contains codons.

What is Antisense Strand?

Antisense strand is the template strand used in the process of transcription. The resulting mRNA and sense strand are complementary to this strand. This strand containsanti-codons.

What is the difference between Sense and Antisense Strand?

During transcription:

Sense Strand:Nucleotides are not linked to sense strand

Antisense Strand:Nucleotides are linked to the antisense strand by hydrogen bonds

Base sequences:

Sense Strand:Base sequences of sense strand are equal to new RNA transcribed

Antisense Strand:Base sequences of antisense strand is complementary to new RNA transcribed.

Image Courtesy:

1.DNA TranscriptionBy Dovelike (Own work) [CC BY-SA 3.0], via Wikimedia Commons

2.Antisense DNA oligonucleotideBy Robinson R – RNAi Therapeutics: How Likely, How Soon? Robinson R PLoS Biology Vol. 2, No. 1, e28 doi:10.1371/journal.pbio.0020028 [CC BY 2.5] via Wikimedia Commons