Chinsky J M, Maa M C, Ramamurthy V, Kellems R E
Verna and Marrs McLean Department of Biochemistry, Baylor College of Medicine, Houston, Texas 77030.
J Biol Chem. 1989 Aug 25;264(24):14561-5.
The mechanism by which the expression of adenosine deaminase (ADA, EC 3.5.4.4) is regulated in murine tissues was analyzed. Elevated levels of the specific activity of this enzyme appeared to correlate directly with steady state levels of ADA mRNA. Transcriptional studies using nuclear run-on experiments revealed a pronounced asymmetric distribution of nascent transcripts across the ADA genome. The ability to detect nascent transcripts downstream of the promoter proximal region varied among tissues and correlated with tissue levels of ADA mRNA and enzymatic activity. These results indicate that processes affecting the elongation of nascent transcripts into completed primary transcripts play a role in tissue-specific expression of ADA.
分析了小鼠组织中腺苷脱氨酶（ADA，EC 3.5.4.4）表达的调控机制。该酶比活性的升高似乎与ADA mRNA的稳态水平直接相关。使用核转录实验的转录研究揭示了新生转录本在ADA基因组上明显的不对称分布。在启动子近端区域下游检测新生转录本的能力在不同组织中有所不同，并且与ADA mRNA的组织水平和酶活性相关。这些结果表明，影响新生转录本延伸为完整初级转录本的过程在ADA的组织特异性表达中起作用。
