  We introduce exclusion models of two distinguishable species of hard rods
with their distinct sites of entry and exit under open boundary conditions. In
the first model both species of rods move in the same direction whereas in the
other two models they move in the opposite direction. These models are
motivated by the biological phenomenon known as Transcriptional Interference.
Therefore, the rules for the kinetics of the models, particularly the rules for
the outcome of the encounter of the rods, are also formulated to mimic those
observed in Transcriptional Interference. By a combination of mean-field theory
and computer simulation of these models we demonstrate how the flux of one
species of rods is completely switched off by the other. Exploring the
parameter space of the model we also establish the conditions under which
switch-like regulation of two fluxes is possible; from the extensive analysis
we discover more than one possible mechanism of this phenomenon.
