  The translation of messenger RNA transcripts to proteins is commonly modeled
as a one-dimensional totally asymmetric exclusion process with extended
particles. Here we focus on the effects of premature termination of translation
through the irreversible detachment of ribosomes. We consider a model where the
detachment is induced by the unsuccessful attempt to move to an occupied site.
The model is exactly solvable in a simplified geometry consisting of the
translation initiation region followed by a single slow site representing a
translation bottleneck. In agreement with recent experimental and computational
studies we find a non-monotonic dependence of the ribosome current on the
initiation rate, but only if the leading particle in a colliding pair detaches.
Simulations show that the effect persists for larger lattices and extended
bottlenecks. In the homogeneous system the ribosome density decays
asymptotically as the inverse square root of the distance to the initiation
site.
