Abstract
Recent experiments at the level of a single cell have shown that gene
expression occurs in abrupt stochastic bursts. Further, in an ensemble
of cells, the levels of proteins produced have a bimodal distribution.
In a large fraction of cells, the gene expression is either off or has
a high value. We propose a stochastic model of gene expression, the
essential features of which are stochasticity and cooperative binding
of RNA polymerase. The model can reproduce the bimodal behavior seen in experiments.
