Signalling from the cell surface to the nucleus.

: Transcriptional initiation is regulated by altering the properties of promoter-specific DNA-binding proteins, such that these proteins either show altered interaction with the basal transcriptional machinery, or show changes in their cytoplasmic/nuclear distribution. Information is passed from the receptor to the transcription factor by a process of post-translational modifications of pathway components. Post-translational modifications can include phosphorylations or dephosphorylations, which are reversible, and proteolysis, which is irreversible. Specificity within a linear signal transduction pathway is preserved by the existence of scaffold proteins, which serve to co-localize many of the factors from a given linear pathway.