Spastic Paraplegia 20 (SPG20)

SPG20 encodes a protein containing a MIT (Microtubule Interacting and Trafficking molecule) domain, and is implicated in regulating endosomal trafficking and mitochondria function. The protein localizes to mitochondria and partially co-localizes with microtubules. Stimulation with epidermal growth factor (EGF) results in protein translocation to the plasma membrane, and the protein functions in the degradation and intracellular trafficking of EGF receptor. Multiple alternatively spliced variants, encoding the same protein, have been identified. Mutations associated with this gene cause autosomal recessive spastic paraplegia 20 (Troyer syndrome). The SPG20 gene produces a 3,402-bp transcript encoding a 72.7-kD, 666-amino acid protein that the authors called spartin (spastic paraplegia autosomal recessive Troyer syndrome).