Alternative titles; symbols
HGNC Approved Gene Symbol: CSRNP1
Cytogenetic location: 3p22.2 Genomic coordinates (GRCh38) : 3:39,141,855-39,154,641 (from NCBI)
Axin, an important regulator of beta-catenin (CTNNB1; 116806), is frequently mutated in human hepatocellular carcinomas, and transduction of the wildtype AXIN1 gene (603816) induces apoptosis in hepatocellular carcinoma cells as well as in colon cancer cells. To investigate the detailed biologic function of axin, Ishiguro et al. (2001) searched on a cDNA microarray for genes whose expression was altered by transfer of wildtype AXIN1 into a colon cancer cell line. They identified a novel gene, designated AXIN1-upregulated (AXUD1), which showed enhanced expression in response to exogenously expressed AXIN1. AXUD1 encodes a putative 589-amino acid protein. Transfection experiments localized AXUD1 mainly to the nuclei. Northern blot analysis detected expression of a 3.2-kb AXUD1 transcript in all human tissues examined, with highest expression in lung, placenta, skeletal muscle, pancreas, and leukocyte. AXUD1 was frequently downregulated in lung, kidney, liver and colon cancers compared with the corresponding normal tissues, suggesting that AXUD1 may have a tumor suppressor function in these organs.
Gingras et al. (2007) cloned mouse Csrnp1, which encodes a 583-amino acid protein with a calculated molecular mass of 62.5 kD. Csrnp1 contains a conserved N-terminal region consisting of a serine-rich motif, a cysteine-rich motif, and a basic domain. Csrnp1 shares 40% amino acid identity with Csrnp2 (620404) and Csrnp3 (620405). Northern blot analysis detected a 3.2-kb transcript in all mouse tissues examined, with highest levels in thymus and lung. Quantitative RT-PCR showed low-level Csrnp2 expression in naive T cells, but expression was strongly induced upon activation. Immunofluorescence assays showed that FLAG-tagged Csrnp1 localized to nuclei in transfected NIH-3T3 fibroblasts.
Ishiguro et al. (2001) determined that the CSRNP1 gene consists of 5 exons.
By radiation hybrid analysis, Ishiguro et al. (2001) mapped the CSRNP1 gene to chromosome 3p22, a region where frequent loss of heterozygosity has been reported in lung, renal, prostate, breast and cervical cancers.
By FISH, Gingras et al. (2007) mapped that the Csrnp1 gene to mouse chromosome 9F3-F4.
Gingras et al. (2007) found that mouse Csrnp1 possessed DNA-binding activity and displayed transcriptional activity in 293T cells.
Gingras et al. (2007) found that Csrnp1 -/- mice were born at the expected mendelian ratio, were indistinguishable from wildtype, and developed normally. Csrnp1 -/- adults were healthy and fertile with no obvious phenotype. Csrnp1 and Csrpn2 double-knockout mice also lacked phenotypic changes. Csrnp1, Csrnp2, and Csrnp3 triple-knockout mice were born at the expected mendelian frequency, but the majority died during the first 48 hours, indicating that the CSRNP genes have potentially redundant functions for perinatal viability.
Gingras, S., Pelletier, S., Boyd, K., Ihle, J. N. Characterization of a family of novel cysteine- serine-rich nuclear proteins (CSRNP). PLoS One 2: e808, 2007. [PubMed: 17726538] [Full Text: https://doi.org/10.1371/journal.pone.0000808]
Ishiguro, H., Tsunoda, T., Tanaka, T., Fujii, Y., Nakamura, Y., Furukawa, Y. Identification of AXUD1, a novel human gene induced by AXIN1 and its reduced expression in human carcinomas of the lung, liver, colon and kidney. Oncogene 20: 5062-5066, 2001. [PubMed: 11526492] [Full Text: https://doi.org/10.1038/sj.onc.1204603]