Cell type-specific transcriptional regulation of the human adenosine deaminase gene.
Cell type-specific transcriptional regulation of the human adenosine deaminase gene.
复制标题
人腺苷脱氨酶基因的细胞类型特异性转录调控。
DOI：
10.1093/nar/17.3.1061
复制
发表时间：
1989
影响因子：
14.9
通讯作者：
Wiginton,DA
中科院分区：
文献类型：
--
作者：
Lattier,DL;States,JC;Hutton,JJ;Wiginton,DA
在T淋巴细胞、B淋巴细胞和皮肤成纤维细胞分离的细胞核中测定了人腺苷脱氨酶（ADA）基因的相对转录率。ADA基因在T细胞中的转录率高于B细胞和成纤维细胞。每个细胞系的相对稳定状态ADA mRNA水平也被确定，这些值被发现与基因的相对转录率相关。因此，控制这种普遍存在的酶的表达的主要机制是在转录水平上。还比较了不同细胞系间ADA酶活性与特定mRNA含量的比值。B淋巴母细胞的比例低于T淋巴母细胞，这表明B淋巴母细胞的蛋白质降解率比T淋巴母细胞高几倍。这一发现与先前对ADA蛋白周转的直接测量一致。与T细胞相比，B细胞中蛋白质转换的差异率提供了调节ADA表达的次要机制。除了转录起始是所有细胞系中稳态ADA mRNA的主要控制机制外，首先内含子延长暂停发生在成纤维细胞中，并且在所研究的所有细胞系中都观察到RNA聚合II和RNA聚合酶ll反义转录的离散区域。
The relative rates of transcription of the human adenosine deaminase (ADA) gene were determined in isolated nuclei from T and B lymphoblasts and skin fibroblasts. ADA gene transcription occurs at higher rates in T cells than in B cells and fibroblasts. Relative steady state ADA mRNA levels were also determined for each cell line, and these values were found to correlate with relative rates of transcription of the gene. Therefore, the primary mechanism for control of expression of this ubiquitous enzyme is at the level of transcription. The ratios of ADA enzymatic activity to specific mRNA content were also compared between cell lines. The B lymphoblasts exhibited lower ratios than did the T lymphoblasts, suggesting that rates of protein degradation were several fold greater in B than in T lymphoblast cell lines. This finding is consistent with previous direct measurements of ADA protein turnover. Differential rates of protein turnover in B as compared to T cells provide a secondary mechanism for the regulation of ADA expression. In addition to transcription initiation being the major control mechanism of steady state ADA mRNA in all cell lines, first intron elongation pausing occurs in fibroblasts, and discrete regions of RNA polymerise II and RNA polymerase lll antisense transcripts are observed in all cell lines studied.