Survival motor neuron (SMN) interacting protein 1 (SIP1) interacts with SMN protein and plays a crucial role in the biogenesis of spliceosomes. There is evidence that the protein is linked to spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis(ALS) in humans[1].

1: Increased expression level of the splicing variant of SIP1 in motor neuron diseases. Aerbajinai W, Ishihara T, Arahata K, Tsukahara T; Int J Biochem Cell Biol 2002;34:699-707. PMID:11943600