Alternative titles; symbols
HGNC Approved Gene Symbol: LZTS3
Cytogenetic location: 20p13 Genomic coordinates (GRCh38): 20:3,162,617-3,173,549 (from NCBI)
By sequencing clones obtained from a size-fractionated human brain cDNA library, Nagase et al. (1998) cloned KIAA0552. The cDNA contains a repetitive element in its 3-prime UTR, and the deduced protein contains 673 amino acids. The translated protein had an apparent molecular mass of 75 kD by SDS-PAGE. RT-PCR detected high expression in brain and kidney, intermediate expression in heart, placenta, ovary, and small intestine, and weak expression in lung, liver, skeletal muscle, pancreas, prostate, and testis. Little to no expression was detected in spleen and thymus.
Wendholt et al. (2006) cloned Prosapip1 from rat brain. The deduced protein contains a coiled-coil domain, a leucine zipper, a C-terminal Fez1 domain, and a C-terminal PDZ domain-binding motif. Western blot analysis showed that Prosapip1 protein levels increased in rat brain after birth and were highest at 3 months of age. Highest levels were in cerebral cortex, cerebellum, and hippocampus. Subcellular fractionation revealed enrichment of Prosapip1 in postsynaptic densities (PSDs). In rat primary hippocampal cultures, Prosapip1 colocalized in PSDs with Prosap2 (SHANK3; 606230).
By yeast 2-hybrid analysis, Wendholt et al. (2006) found that rat Prosapip1 interacted with Prosap2. Deletion analysis showed that the PDZ domain-binding motif of Prosapip1 bound the PDZ domain of Prosap2. Pull-down assays and coimmunoprecipitation of rat brain homogenates confirmed the Prosapip1-Prosap2 interaction. Prosapip1 formed homodimers and heteromultimers with PSD-Zip70 (LZTS1; 606551), and both proteins recruited SPAR (SIPA1L1) to synapses.
By radiation hybrid analysis, Nagase et al. (1998) mapped the KIAA0552 gene to chromosome 20. Wendholt et al. (2006) stated that the PROSAPIP1 gene maps to chromosome 20p13.
Nagase, T., Ishikawa, K., Miyajima, N., Tanaka, A., Kotani, H., Nomura, N., Ohara, O. Prediction of the coding sequences of unidentified human genes. IX. The complete sequences of 100 new cDNA clones from brain which can code for large proteins in vitro. DNA Res. 5: 31-39, 1998. [PubMed: 9628581] [Full Text: https://doi.org/10.1093/dnares/5.1.31]
Wendholt, D., Spilker, C., Schmitt, A., Dolnik, A., Smalla, K.-H., Proepper, C., Bockmann, J., Sobue, K., Gundelfinger, E. D., Kreutz, M. R., Boeckers, T. M. ProSAP-interacting protein 1 (ProSAPiP1), a novel protein of the postsynaptic density that links the spine-associated Rap-Gap (SPAR) to the scaffolding protein ProSAP2/Shank3. J. Biol. Chem. 281: 13805-13816, 2006. [PubMed: 16522626] [Full Text: https://doi.org/10.1074/jbc.M601101200]