Sense (molecular biology)

Overview of sense and antisense in molecular biology

Sense in Molecular Biology

In molecular biology, the term "sense" refers to the orientation of a nucleic acid strand, particularly in relation to its ability to encode a protein. The concept of sense is crucial for understanding how genes are expressed and how RNA molecules are synthesized and function.

Sense and Antisense Strands

In the context of DNA, the sense strand is the segment of double-stranded DNA that has the same sequence as the messenger RNA (mRNA), which is translated into protein. The sense strand is also known as the "coding strand" because its sequence corresponds directly to the sequence of the mRNA transcript, except that in DNA, thymine (T) is present instead of uracil (U).

The complementary strand to the sense strand is called the "antisense strand" or "template strand." This strand serves as the template for RNA polymerase during the process of transcription, where the mRNA is synthesized. The antisense strand is complementary to both the sense strand and the mRNA.

File:Antisense DNA oligonucleotide.png

Antisense DNA oligonucleotide

Transcription and Translation

During transcription, the antisense strand of DNA is used as a template to produce a complementary RNA strand. This RNA strand is the mRNA, which carries the genetic information from the DNA to the ribosome, where it is translated into a protein. The ribosome reads the mRNA in sets of three nucleotides, called codons, each of which specifies a particular amino acid.

The sense strand, while not directly involved in the transcription process, is important because it contains the actual genetic code that determines the sequence of amino acids in the protein.

Antisense Technology

Antisense technology involves the use of synthetic antisense oligonucleotides to bind to specific mRNA molecules, thereby blocking their translation into protein. This approach can be used to inhibit the expression of specific genes and has potential therapeutic applications in treating diseases caused by overexpression of certain genes.

Related Pages

• DNA
• RNA
• Transcription (biology)
• Translation (biology)
• Gene expression
• Antisense therapy