Shi M, Yan X, Ryan D H, Harris R B
Pennington Biomedical Research Center, Baton Rouge, LA, USA.
Brain Res Bull. 2000 Oct;53(3):317-24. doi: 10.1016/s0361-9230(00)00349-x.
Urocortin (UCN) has 45% sequence homology with corticotropin releasing factor (CRF) and binds to CRF receptors. We used reverse-transcriptase-polymerase chain reaction to demonstrate the presence of UCN RNA in various brain regions and in peripheral tissues. Ribonuclease protection assay (RPA) using sense and antisense riboprobes demonstrated the presence of a naturally occurring antisense UCN RNA transcript in a number of tissues. Northern blot indicated that the antisense transcript was the same size as sense UCN. RPA, using probes that covered bases 1 to 560 of 579 bp sequence of rat UCN, indicated that the antisense sequence was complementary to sense UCN but did not contain an open reading frame. Sense and antisense UCN RNA were co-expressed in all tissues that contained levels of either transcript detectable by RPA. Sense RNA expression was greater than antisense in the midbrain, the two transcripts were expressed equally in the hypothalamus and antisense was expressed at higher levels than sense in the liver, heart, and skeletal muscle. Antisense RNA expression was stress responsive, suggesting that it may play a role in regulating transcription or translation of UCN mRNA.
尿皮质素（UCN）与促肾上腺皮质激素释放因子（CRF）有45%的序列同源性，并能与CRF受体结合。我们使用逆转录聚合酶链反应来证明UCN RNA在各个脑区和外周组织中的存在。使用正义和反义核糖探针的核糖核酸酶保护分析（RPA）证明了在许多组织中存在天然存在的反义UCN RNA转录本。Northern印迹表明反义转录本与正义UCN大小相同。使用覆盖大鼠UCN 579 bp序列中第1至560个碱基的探针进行的RPA表明，反义序列与正义UCN互补，但不包含开放阅读框。正义和反义UCN RNA在所有含有可通过RPA检测到的任何一种转录本水平的组织中共同表达。在中脑，正义RNA表达高于反义；在下丘脑，两种转录本表达水平相当；在肝脏、心脏和骨骼肌中，反义表达水平高于正义。反义RNA表达对压力有反应，表明它可能在调节UCN mRNA的转录或翻译中发挥作用。
