Noonan Ferrin C, Goodfellow Paul J, Staloch Lora J, Mutch David G, Simon Theodore C
Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA.
Genomics. 2003 Jan;81(1):58-66. doi: 10.1016/s0888-7543(02)00023-x.
The homeodomain transcription factor EMX2 is critical for central nervous system and urogenital development. In addition, EMX2 maps to a region of allelic deletion corresponding to a putative endometrial tumor suppressor at 10q26. We now report another polyadenylated transcript that is transcribed on the strand opposite to EMX2 and overlaps with the EMX2 transcript. This transcript was designated EMX2OS (OS, opposite strand), and an orthologous transcript present at the murine Emx2 locus was designated Emx2os. Alternative splicing to generate transcripts with varying 5' sequences was detected in the human but not the mouse. Neither ortholog contains a significant open reading frame, nor is primary sequence conserved between the two species. The sense and antisense transcripts display coordinate expression in that EMX2 and EMX2OS are abundant in normal postmenopausal endometrium, reduced in premenopausal endometrium, and absent or reduced in a majority of primary endometrial tumors. EMX2, EMX2OS, Emx2, and Emx2os are abundant in the uterine endometrium, with sense and antisense transcripts exhibiting identical expression patterns. Conservation of functional human and murine EMX2 antisense genes, of overlap between the sense and the antisense transcripts, and of identical cellular expression patterns suggests a biological function for EMX2OS, presumably to regulate EMX2.
同源结构域转录因子EMX2对中枢神经系统和泌尿生殖系统的发育至关重要。此外，EMX2定位于10q26处与假定的子宫内膜肿瘤抑制因子相对应的等位基因缺失区域。我们现在报告另一种多聚腺苷酸化转录本，它在与EMX2相反的链上转录，并与EMX2转录本重叠。该转录本被命名为EMX2OS（OS，反义链），在小鼠Emx2基因座处存在的直系同源转录本被命名为Emx2os。在人类中检测到可变剪接产生具有不同5'序列的转录本，但在小鼠中未检测到。两个直系同源物均不包含明显的开放阅读框，且两个物种之间的一级序列也不保守。正义和反义转录本表现出协同表达，即EMX2和EMX2OS在正常绝经后子宫内膜中丰富，在绝经前子宫内膜中减少，并且在大多数原发性子宫内膜肿瘤中不存在或减少。EMX2、EMX2OS、Emx2和Emx2os在子宫内膜中丰富，正义和反义转录本表现出相同的表达模式。人类和小鼠功能性EMX2反义基因的保守性、正义和反义转录本之间的重叠以及相同的细胞表达模式表明EMX2OS具有生物学功能，推测是调节EMX2。
