AIPL1 (aryl-hydrocarbon interacting proteinlike 1), described by Sohocki et al. , was the fourth of the LCA genes to be identified and accounts for 3.4-11% [24, 48, 66, 124] of cases. It has also been identified as putatively causative in autosomal dominant cone-rod dystrophy and retinitis pigmentosa (RP)  (http://www.retina-international.org/sci-news/ aipl1mut.htm), though Cremers  has expressed some doubt about this.
The AIPL1 gene (located on 17p13.2) encodes a 384-aminoacid protein that contains three tetratricopeptide (TPR) motifs. TPR domains are sites of protein-protein interaction, and it is thought that the AIPL1 protein, through this motif, interacts and aids in the processing of farnesylated proteins  which are responsible for attachment to cell membranes, in other words, maintaining photoreceptor architecture.
AIPL1 has also been shown to interact with NEDD8 ultimate buster-1 (NUB1), which is an interferon inducible protein; both NUB1 and
AIPL1 are expressed within the developing cone and rod photoreceptors but co-localise solely within the rods of the mature retina [2,123,139]. This suggests that AIPL1 is essential for the normal development of photoreceptor cells. NUB1 is located predominantly within the nuclear component of cells as compared to AIPLi,which is largely cytoplasmic [137,139]. It has now been shown that AIPL1 can modulate protein translocation through enhanced farnesylation, and acts in a chaperone-like manner escorting prenylated proteins to their target membranes, suggesting that AIPL1 is an important modulator of NUBi cellular function . AIPLi mutations implicated in LCA have been shown in vitro not to interact with NUB1 suggesting that this lack of interaction may be a key factor in the abnormal retinal function seen in the LCA retina .
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