2. bow down-bend one's knee or body, or lower one's head; He bowed before the King; She bowed her head in shame. bow. conge, congee-perform a ceremonious bow. gesticulate, gesture, motion-show, express or direct through movement; He gestured his desire to leave.
Sections. Definition. Gene regulation refers to the mechanisms that act to induce or repress the expression of a gene. These include structural and chemical changes to the genetic material, binding of proteins to specific DNA elements to regulate transcription, or mechanisms that modulate translation of mRNA. News and Comment.
One of the central questions of modern biology is what controls gene expression. As we have previously described, genes must be turned on at the right time, in the right cell. To a first approximation, all the cells in an organism contains the same DNA (with the exception of germ cells and immune cells).ince these sequences are in the DNA (the molecule that is transcribed), they are called cis-regulatory sequences. The second mechanism involves an increase in the elaboration and complexity of proteins (trans-regulatory elements) that regulate gene expression in more complex organisms..