  We study a framework where the hypothesis of a minimum length in space-time
is complemented with the notion of reference frame invariance. It turns out
natural to interpret the action of the obtained reference frame transformations
in the context of doubly special relativity. As a consequence of this formalism
we find interesting connections between the minimum length properties and the
modified velocity-energy relation for ultra-relativistic particles. For example
we can predict the ratio between the minimum lengths in space and time using
the results from OPERA about superluminal neutrinos.
