We know for some time, how the cellular transporters directed towards the periphery (kinesins, the ones carrying something red in the animation below) are walking their (microtubule) cellular highways. Now, thanks to two recent publications (DeWitt et al., Science 335, 221- 225 and Qiu et al., Nature Struct Mol Biol http://dx.doi.org/10.1038/nsmb) we start to learn, how the transporters directed towards the nucleus might walk. (The latter are called dyneins and are carrying something blue in the animation below.) As you can see, they seem to use a different gear. Information on this topic can also be obtained from a recent summary in the journal “Nature” (Walter and Diez, Nature 482, 44-45).
Walking the cellular highways