Pott U, Colello R J, Schwab M E
Brain Research Institute, University of Zurich, Switzerland.
Brain Res Mol Brain Res. 1996 May;38(1):109-21. doi: 10.1016/0169-328x(95)00340-x.
The myelination of nerve fibers is essential for the function of the vertebrate nervous system as a prerequisite for fast saltatory conduction of action potentials. In the central nervous system (CNS), myelin is produced by oligodendrocytes. In order to identify gene regulatory proteins involved in the differentiation of this glial cell type or in the expression of myelin-specific genes, we have constructed a cDNA library from a highly enriched population of rat oligodendrocytes and screened this library for members of the Krüppel family of Cys2/His2 zinc finger proteins. One of the identified clones, named rKr1, encodes a novel protein of 650 amino acids which contains 12 carboxy-terminal zinc finger domains and an amino-terminal acidic domain. On Northern blots, a single rKr1 mRNA of 4.3 kb is detected. This message is present in all adult rat tissues tested, with the highest levels found in the CNS and testis. In situ hybridization on the P15 brain revealed that the transcript is expressed in differentiated oligodendrocytes and in subtypes of neurons. Particularly high message levels are found in motor neurons of the brainstem and the spinal cord. The modular structure of the rKr1 protein, in which a potential DNA binding region (the zinc fingers) is combined with a putative activation domain (the acidic region), suggests a function as sequence-specific transcriptional activator.
神经纤维的髓鞘形成对于脊椎动物神经系统的功能至关重要，它是动作电位快速跳跃式传导的前提条件。在中枢神经系统（CNS）中，髓鞘由少突胶质细胞产生。为了鉴定参与这种神经胶质细胞类型分化或髓鞘特异性基因表达的基因调控蛋白，我们从高度富集的大鼠少突胶质细胞群体构建了一个cDNA文库，并筛选该文库以寻找Cys2/His2锌指蛋白的Krüppel家族成员。其中一个鉴定出的克隆，命名为rKr1，编码一种650个氨基酸的新蛋白，该蛋白含有12个羧基末端锌指结构域和一个氨基末端酸性结构域。在Northern印迹上，检测到一条4.3 kb的单一rKr1 mRNA。该信使RNA存在于所有测试的成年大鼠组织中，在中枢神经系统和睾丸中含量最高。对P15脑进行原位杂交显示，该转录本在分化的少突胶质细胞和神经元亚型中表达。在脑干和脊髓的运动神经元中发现特别高的信使RNA水平。rKr1蛋白的模块化结构，其中一个潜在的DNA结合区域（锌指）与一个假定的激活结构域（酸性区域）相结合，表明其具有序列特异性转录激活因子的功能。
