Gnas

This locus has a highly complex imprinted expression pattern. It gives rise to maternally, paternally, and biallelically expressed transcripts that are derived from four alternative promoters and 5' exons. Some transcripts contain a differentially methylated region (DMR) at their 5' exons, which is commonly found in imprinted genes and correlates with transcript expression. This gene has an antisense transcript. One of the transcripts produced from this locus, and the antisense transcript, are both paternally expressed noncoding RNAs, and may regulate imprinting in this region. In addition, one of the transcripts contains a second overlapping ORF, which encodes a structurally unrelated protein - Alex. Alternative splicing of downstream exons is also observed, which results in different forms of the stimulatory G-protein alpha subunit, a key element of the classical signal transduction pathway linking receptor-ligand interactions with the activation of adenylyl cyclase and a variety of cellular reponses. Additional transcript variants have been found for this gene, but the full-length nature and/or biological validity of some variants have not been determined. [provided by RefSeq, Jun 2015]

此基因座呈现出高度复杂的印记表达模式。它衍生出母系、父系以及双等位基因表达的转录本，这些转录本源自四个不同的启动子和5'外显子。部分转录本在其5'外显子含有差异甲基化区域（DMR），该区域常见于印记基因，并与转录本的表达到相联系。该基因存在一个反义转录本。由该基因座产生的其中一个转录本及其反义转录本均为父系表达的非编码RNA，可能调节该区域的印记。此外，其中一个转录本含有第二个重叠的开放阅读框（ORF），编码一种结构上不相关的蛋白质——Alex。下游外显子的选择性剪接也被观察到，这导致了兴奋性G蛋白α亚单位的多种形式，该亚单位是经典信号转导途径的关键元素，该途径将受体-配体相互作用与腺苷酸环化酶的激活以及多种细胞反应联系起来。此外，还发现了该基因的额外转录本变体，但其中一些变体的全长性质和/或生物学有效性尚未确定。[由RefSeq提供，2015年6月]