Plus (+) and Minus (-) DNA & Sense RNA

The DNA in the 5’ (PO₄ end) to 3’ (OH end) orientation is the known as the plus (or sense) strand of DNA. The complimentary DNA strand (which is antiparallel) must be in the opposite orientation, 3’ to 5’ and is known as the minus (antisense) strand of DNA. (image modified from: http://upload.wikimedia.org)

In order to change the instructions recorded on DNA into proteins, the DNA strand must denature (unzip). The minus strand is used as a template to transcribe mRNA.

The resulting mRNA is complimentary to the minus strand of DNA.

The mRNA is analogous to the plus strand of DNA. It has polarity (it is oriented in the same 5’ to 3’ direction) as the plus strand of DNA.

Such mRNA is sense RNA and it encodes for the amino acid (aa) sequence of a protein.