Activation brought about by something on the same cell or on the same chromosome. There are examples of cis-activation of adhesion molecules through protein–protein contacts that occur in the plane of the membrane but do not occur if the two molecules are in different cells. Cis-activation of a gene is brought about by activators binding to upstream regions of the chromosome, whereas trans-activation would involve a diffusible product. Compare transactivation.
Subjects: Medicine and Health.