Because the members of the Kinesin-1 subfamily of motor proteins are important in long range anterograde axonal transport and mutations in this family have been linked to neurodegenerative diseases like hereditary spastic paraplegia (HSP), which is most commonly associated with spastin mutations, Khc of Kinesin-1 serves as an excellent candidate for apical protein delivery along the newly identified microtubules of the developing Drosophila photoreceptor cells [13]. Here, IMMT is linked to hereditary spastic paraplegia.