Primus R J, Jacobs A A, Gallager D W
Department of Psychiatry, Yale University, New Haven, CT.
Brain Res Mol Brain Res. 1992 Jul;14(3):179-85. doi: 10.1016/0169-328x(92)90172-8.
The ratio of mRNA not selected for polyadenylation (non-poly(A)+ selected) to mRNA selected for polyadenylation (poly(A)+) for the beta 1, alpha 1 and gamma 2 subunits of the GABAA receptor complex was examined in rats as a function of age. RNA was extracted from whole brain of rats that were either 0, 1, 3, 5 or over 60 days of postnatal age. Poly(A)+ mRNA was purified by oligo(dT)-cellulose chromatography. Non-poly(A)+ selected mRNA and poly(A)+ mRNA for the GABAA receptor beta 1, alpha 1 and gamma 2 subunits were examined by Northern blot analysis using cDNA probes specific for these subunits. Levels of GABAA receptor beta 1 subunit mRNA were also examined by solution hybridization analysis with a beta 1 riboprobe. Analysis of Northern blots revealed that levels of poly(A)+ beta 1 subunit mRNA were highest at 0 days of age, but decreased and reached adult levels by 5 days of postnatal age. However, levels of the beta 1 subunit message extracted from non-poly(A)+ selected mRNA were not significantly different at any of the ages examined, suggesting the existence of a population of beta 1 subunit mRNA that is not polyadenylated. The age-related discrepancy between beta 1 subunit levels measured in non-poly(A)+ selected mRNA and poly(A)+ mRNA was also observed using solution hybridization analysis. In contrast, levels of both non-poly(A)+ selected mRNA and poly(A)+ mRNA for the alpha 1 subunit of the GABAA complex increased from 0 days of age to adulthood. Similarly, levels of both non-poly(A)+ selected mRNA and poly(A)+ mRNA for the GABAA receptor gamma 2 subunit increased with age.(ABSTRACT TRUNCATED AT 250 WORDS)
在大鼠中，研究了γ-氨基丁酸A型（GABAA）受体复合物β1、α1和γ2亚基未被选择进行聚腺苷酸化的mRNA（非聚腺苷酸化（A）+选择的mRNA）与被选择进行聚腺苷酸化的mRNA（聚腺苷酸化（A）+）的比例随年龄的变化。从出生后0、1、3、5天或60天以上的大鼠全脑中提取RNA。通过寡聚（dT）-纤维素色谱法纯化聚腺苷酸化（A）+mRNA。使用针对这些亚基的cDNA探针，通过Northern印迹分析检测GABAA受体β1、α1和γ2亚基的非聚腺苷酸化（A）+选择的mRNA和聚腺苷酸化（A）+mRNA。还使用β1核糖探针通过溶液杂交分析检测GABAA受体β1亚基mRNA的水平。Northern印迹分析显示，聚腺苷酸化（A）+β1亚基mRNA的水平在0天时最高，但在出生后5天时下降并达到成年水平。然而，从非聚腺苷酸化（A）+选择的mRNA中提取的β1亚基信息水平在任何检测的年龄都没有显著差异，这表明存在未进行聚腺苷酸化的β1亚基mRNA群体。使用溶液杂交分析也观察到了非聚腺苷酸化（A）+选择的mRNA和聚腺苷酸化（A）+mRNA中β1亚基水平与年龄相关的差异。相比之下，GABAA复合物α1亚基的非聚腺苷酸化（A）+选择的mRNA和聚腺苷酸化（A）+mRNA的水平从0天龄到成年期都增加。同样，GABAA受体γ2亚基的非聚腺苷酸化（A）+选择的mRNA和聚腺苷酸化（A）+mRNA的水平都随年龄增加。（摘要截短至250字）
