Alternative titles; symbols
HGNC Approved Gene Symbol: GNG12-AS1
Cytogenetic location: 1p31.3 Genomic coordinates (GRCh38) : 1:67,832,288-68,202,987 (from NCBI)
Long noncoding RNAs (lncRNAs), like GNG12AS1, contain over 200 bp and are predicted to regulate gene expression (Niemczyk et al., 2013).
By RT-PCR and 5-prime and 3-prime RACE, Niemczyk et al. (2013) found that GNG12AS1 was subject to extensive and complex splicing, resulting in 38 variants in human tissues and cells. RT-PCR of 19 human tissues detected highest GNG12AS1 expression in pancreas, with lower expression in most other tissues. Little to no expression was detected in brain, esophagus, heart, and thymus. GNG12AS1 expression was higher in normal human breast than in matched breast tumor tissue.
Niemczyk et al. (2013) determined that the GNG12AS1 gene spans 370 kb and contains 17 exons. GNG12AS1 contains a single transcriptional start site within exon 1 and 3 polyadenylation sites at its 3-prime end. An intronic region of GNG12AS1 contains the DIRAS3 gene (605193) on the opposite strand.
By genomic sequence analysis, Niemczyk et al. (2013) mapped the GNG12AS1 gene to chromosome 1p31. The 5-prime end of GNG12AS1 overlaps the promoter region of the GNG12 gene (615405) on the opposite strand, and the 3-prime prime end of GNG12AS1 overlaps the WLS gene (611514) on the same strand. The DIRAS3 gene is located within an intronic region of GNG12AS1 on the opposite strand.
Niemczyk et al. (2013) found that the major GNG12AS1 splice variants were biallelically expressed in normal breast epithelial cell lines and placenta. Some minor GNG12AS1 variants appeared to be subject to imprinting and were expressed from the maternal allele. Niemczyk et al. (2013) noted that the DIRAS3 gene, which is found within an intron of the GNG12AS1 gene, is subject to imprinting and is silenced on the maternal allele in normal breast epithelia. They found that expression of GNG12AS1 was controlled by differential methylation of a CpG island at the DIRAS3 locus. In breast cancer cell lines, GNG12AS1 was monoallelically expressed, concomitant with loss of DIRAS3 imprinting.
Niemczyk, M., Ito, Y., Huddleston, J., Git, A., Abu-Amero, S., Caldas, C., Moore, G. E., Stojic, L., Murrell, A. Imprinted chromatin around DIRAS3 regulates alternative splicing of GNG12-AS1, a long noncoding RNA. Am. J. Hum. Genet. 93: 224-235, 2013. [PubMed: 23871723] [Full Text: https://doi.org/10.1016/j.ajhg.2013.06.010]