Alternative titles; symbols
HGNC Approved Gene Symbol: POLDIP3
Cytogenetic location: 22q13.2 Genomic coordinates (GRCh38) : 22:42,583,721-42,614,883 (from NCBI)
By yeast 2-hybrid screen of a human placental cDNA library using POLD2 (600815) as bait, Liu et al. (2003) cloned POLDIP3, which they called PDIP46.
By yeast 2-hybrid screen of a mouse embryonic cDNA library using S6k1 (RPS6KB1; 608938) as bait, followed by database analysis, screen of a human T cell cDNA library, and 5-prime RACE, Richardson et al. (2004) cloned human and mouse POLDIP3, which they called SKAR. The encoded protein contains a C-terminal RNA recognition motif (RRM) with highest homology to the ALY (THOC4; 604171)/REF family of RNA-binding proteins. They identified a SKAR-alpha isoform of 421 amino acids with a predicted molecular mass of 46 kD and a SKAR-beta isoform of 392 amino acids with a predicted molecular mass of 43 kD. Northern blot analysis of human tissues detected ubiquitous expression with highest levels in brain, heart, skeletal muscle, and kidney. Immunofluorescence microscopy showed nuclear localization both in nucleoplasm and in punctate structures.
Richardson et al. (2004) showed that SKAR interacted with and is a substrate for S6K1 but not S6K2 (RPS6KB2; 608939). SKAR was phosphorylated by S6K1 in vitro on sites that are mitogen-regulated and rapamycin-sensitive in vivo. RNAi-mediated reduction of S6K1 in HEK293 cells resulted in decreased SKAR phosphorylation, and reduction of SKAR by RNAi in human osteosarcoma cells resulted in decreased cell size, suggesting that SKAR is a target of S6K1 in cell growth control.
Richardson et al. (2004) noted that the POLDIP3 gene to chromosome 22.
Liu, L., Rodriguez-Belmonte, E. M., Mazloum, N., Xie, B., Lee, M. Y. W. T. Identification of a novel protein, PDIP38, that interacts with the p50 subunit of DNA polymerase delta and proliferating cell nuclear antigen. J. Biol. Chem. 278: 10041-10047, 2003. [PubMed: 12522211] [Full Text: https://doi.org/10.1074/jbc.M208694200]
Richardson, C. J., Broenstrup, M., Fingar, D. C., Julich, K., Ballif, B. A., Gygi, S., Blenis, J. SKAR is a specific target of S6 kinase 1 in cell growth control. Curr. Biol. 14: 1540-1549, 2004. [PubMed: 15341740] [Full Text: https://doi.org/10.1016/j.cub.2004.08.061]