in biotechnology
  1. The cellular production of the protein encoded by a particular gene. The process includes transcription of DNA, processing of the resulting mRNA product and its translation into an active protein.
  2. A recombinant gene inserted into a host cell by means of a vector is said to be expressed if the synthesis of the encoded protein can be demonstrated.
PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 153 (