Differential regulation of microtubule‐associated protein 1B (MAP1B) in rat CNS and PNS during development
Differential regulation of microtubule‐associated protein 1B (MAP1B) in rat CNS and PNS during development
复制标题
DOI：
10.1002/(sici)1097-4547(19970801)49:3
复制
发表时间：
1997-08
影响因子：
4.2
通讯作者：
D. Ma;F. Nothias;L. Boyne;I. Fischer
中科院分区：
文献类型：
--
作者：
D. Ma;F. Nothias;L. Boyne;I. Fischer
MAP 1B是生长轴突的主要细胞骨架蛋白，在脑发育过程中受到强烈调控。本研究比较了MAP 1B mRNA、蛋白质及其磷酸化亚型在脊髓和背根神经节（DRG）与脑中的表达。在脊髓和大脑中，MAP 1B mRNA水平在发育的早期阶段最高，在出生后的发育过程中下降了几倍，并在成人中保持较低水平。相反，在DRG发育过程中，MAP 1B mRNA水平没有显著变化，并且在成人中保持较高水平。MAP 1B蛋白在脑和脊髓中的表达与其mRNA的表达水平呈平行下降趋势。DRG中的蛋白质水平保持相对较高，但坐骨神经中的蛋白质水平下降。磷酸化的MAP 1B在大脑，脊髓和坐骨神经发育的早期阶段以高水平表达，并在出生后迅速下降至检测不到的水平，除了坐骨神经，它仍然是可检测的。免疫组织化学分析显示，磷酸化的MAP 1B是缺席的DRG细胞体在所有阶段，但存在于DRG的轴突和运动神经元在脊髓和坐骨神经。免疫染色也证实了蛋白质印迹分析表明，MAP 1B最初是丰富的脊髓内，但在后期阶段只存在于运动神经元和DRG神经元的中央过程。这些结果反映了MAP 1B亚型在不同发育阶段和神经系统不同区域的差异分布。神经科学杂志Res. 49：319-332，1997.© 1997 Wiley利斯公司
MAP1B is a major cytoskeletal protein in growing axons and is strongly regulated during brain development. The present studies compare the expression of MAP1B mRNA, the protein, and its phosphorylated isoform in spinal cord and dorsal root ganglia (DRGs) with brain. In spinal cord and brain, MAP1B mRNA levels were highest in early stages of development, decreased several fold during postnatal development, and remained low in adults. In contrast, there were no significant changes of MAP1B mRNA levels during development of DRG and they remained high in adults. The levels of MAP1B protein decreased in brain and spinal cord in parallel with the changes of their mRNA. The protein levels in DRG remained relatively high but declined in the sciatic nerve. Phosphorylated MAP1B was expressed in high levels during the early stages of development in brain, spinal cord, and sciatic nerve and decreased rapidly to undetectable levels postnatally except for sciatic nerve where it remained detectable. Immunohistochemical analysis showed that phosphorylated MAP1B was absent from DRG cell bodies at all stages but was present in axons of DRG and motor neurons in both spinal cord and sciatic nerve. Immunostaining also confirmed Western blot analysis indicating that MAP1B was initially abundant within the spinal cord but was at later stages present only in motor neurons and the central processes of DRG neurons. These results reflect differential distribution of MAP1B isoforms at different stages of development and in different regions of the nervous system. J. Neurosci. Res. 49:319–332, 1997. © 1997 Wiley‐Liss, Inc.