3 Stochastic modeling of mammalian gene expression 12 3.1 Extension of the Telegraph model: the promoter cycle . . . . . . . . . . . . . . . . . 12 3.2 Likelihood calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.2.1 Transition probabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.2.2 Efficient likelihood computation . . . . . . . ....