Here's a breakdown of the process:

1. Transcription: RNA polymerase binds to a specific region on the DNA called the promoter, which signals the start of a gene.

2. Unwinding: The enzyme unwinds the DNA double helix, separating the two strands.

3. Base Pairing: RNA polymerase uses one strand of the DNA as a template to build a complementary mRNA molecule. Instead of thymine (T), mRNA uses uracil (U).

4. Elongation: RNA polymerase moves along the DNA strand, adding nucleotides to the growing mRNA molecule.

5. Termination: When RNA polymerase reaches a termination signal on the DNA, it detaches from the DNA and the newly synthesized mRNA molecule is released.

This mRNA molecule then travels out of the nucleus and into the cytoplasm, where it is translated into a protein.