Delays, large and small, in gene expression

The use of large delays (on the minute-to-hours timescales) to represent transcription and translation times is now well established. A variety of theoretical approaches have been taken to justify the introduction of these delays in models of gene expression. The potential dynamical consequences of large delays are also well known, including the potential for delay-induced instabilities. What is perhaps less well-known is that short delays may also be important. Specifically, relatively short delays associated with clearing binding sites for an RNA polymerase or for a ribosome can have surprisingly large effects on the dynamics of a biochemical system. In this talk, I will discuss the theoretical justification and some dynamical effects of delays in gene expression, large and small.