Liu F, Huang Y-F, Kream B E
Department of Medicine, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030, USA.
Calcif Tissue Int. 2005 Aug;77(2):91-5. doi: 10.1007/s00223-005-0003-1. Epub 2005 Jul 28.
CREM, the cyclic adenosine monophosphate (cAMP) responsive element modulator, belongs to a multigene family of cAMP-responsive transcription factors. CREM encodes a variety of different isoforms by utilizing four promoters and a complex pattern of alternative messenger ribonucleic acid (mRNA) splicing. We showed previously that parathyroid hormone induces the CREM P2 promoter products known as ICER (inducible cAMP early repressor) in osteoblasts. Herein we report that osteoblasts also express at least 15 CREM transcripts initiated from the P1 promoter, including 7 novel transcripts that result from alternative splicing. It is of interest that we found that CREM-X contains both exon theta1, previously identified only in P3 promoter products, and a new exon termed L, which is located upstream of exon theta1.
CREM，即环磷酸腺苷（cAMP）反应元件调节剂，属于cAMP反应转录因子的多基因家族。CREM通过利用四个启动子和复杂的可变信使核糖核酸（mRNA）剪接模式，编码多种不同的亚型。我们之前表明，甲状旁腺激素可诱导成骨细胞中称为ICER（诱导型cAMP早期阻遏物）的CREM P2启动子产物。在此我们报告，成骨细胞还表达至少15种从P1启动子起始的CREM转录本，包括7种由可变剪接产生的新转录本。有趣的是，我们发现CREM-X既包含先前仅在P3启动子产物中鉴定出的外显子theta1，还包含一个位于外显子theta1上游的名为L的新外显子。
