Moorman A F, de Boer P A, Geerts W J, van den Zande L, Lamers W H, Charles R
Department of Anatomy and Embryology, University of Amsterdam, The Netherlands.
J Histochem Cytochem. 1988 Jul;36(7):751-5. doi: 10.1177/36.7.2898495.
We studied the distribution of the mRNAs for carbamoylphosphate synthetase (ammonia) and glutamine synthetase in frozen sections of adult rat liver by in situ hybridization to [35S]-labeled cDNA probes. The density of silver grains resulting from hybridization to the labeled cDNA probe for carbamoylphosphate synthetase is highest around the portal venules, decreases towards the central venule, and is virtually absent from an area two to three cells wide that lines the central venules in which mRNA for glutamine synthetase is predominantly localized. Therefore, both mRNAs show the same complementary distribution within the liver acinus that was found for the proteins they encode, demonstrating that compartmentalization of the expression of these enzymes is controlled at a pretranslational level. In addition, we found that carbamoylphosphate synthetase mRNA is present mainly in the epithelium of the crypts of the proximal part of the small intestine, whereas carbamoylphosphate synthetase protein is present in the epithelium of both crypts and villi.
我们通过与[35S]标记的cDNA探针进行原位杂交，研究了成年大鼠肝脏冰冻切片中氨甲酰磷酸合成酶（氨）和谷氨酰胺合成酶的mRNA分布。与氨甲酰磷酸合成酶标记cDNA探针杂交产生的银颗粒密度在门静脉小分支周围最高，向中央静脉逐渐降低，并且在中央静脉周围由两到三个细胞宽的区域几乎不存在，而谷氨酰胺合成酶的mRNA主要定位于该区域。因此，这两种mRNA在肝腺泡内呈现出与它们所编码蛋白质相同的互补分布，表明这些酶表达的区域化在翻译前水平受到控制。此外，我们发现氨甲酰磷酸合成酶mRNA主要存在于小肠近端隐窝的上皮细胞中，而氨甲酰磷酸合成酶蛋白则存在于隐窝和绒毛的上皮细胞中。
