Transcription

A messenger RNA strand (mRNA) is produced complementary to a DNA strand, but instead of Thymine (T) there is Uracil (U). The mRNA will leave a cell's nucleus.

RNA polymerases will read a relevant portion of one of the DNA strands. Since it produces the complement, the DNA strand that is read is called the noncoding, anticoding or antisense strand.

The other DNA strand is known as the coding or sense strand. It is the same as the produced RNA strand, but base T is replaced by U.

The antisense strand is transcribed from 3' to 5', so the RNA is produced from 5' to 3'.

A gene's exons may overlap with another gene's exons. This can happen on the same or opposite strand.

mRNA will reach a ribosome which the translates it into a polypeptide.

References

The Information in DNA Is Decoded by Transcription from Essentials of Genetics.

understanding bioinformatics page 11.