Fukada M, Watakabe I, Yuasa-Kawada J, Kawachi H, Kuroiwa A, Matsuda Y, Noda M
Division of Molecular Neurobiology, National Institute for Basic Biology, and Department of Molecular Biomechanics, Graduate University for Advanced Studies, Okazaki 444-8585, Japan.
J Biol Chem. 2000 Dec 1;275(48):37957-65. doi: 10.1074/jbc.M003277200.
The CRMP (collapsin response mediator protein) family is thought to play key roles in growth cone guidance during neural development. The four members (CRMP1-4) identified to date have been demonstrated to form hetero-multimeric structures through mutual associations. In this study, we cloned a novel member of this family, which we call CRMP5, by the yeast two-hybrid method. This protein shares relatively low amino acid identity with the other CRMP members (49-50%) and also with dihydropyrimidinase (51%), whereas CRMP1-4 exhibit higher identity with each other (68-75%), suggesting that CRMP5 might be categorized into a third subfamily. The mouse CRMP5 gene was located at chromosome 5 B1. Northern blot and in situ hybridization analyses indicated that CRMP5 is expressed throughout the nervous system similarly to the other members (especially CRMP1 and CRMP4) with the expression peak in the first postnatal week. Association experiments using the yeast two-hybrid method and co-immunoprecipitation showed that CRMP5 interacts with dihydropyrimidinase and all the CRMPs including itself, except for CRMP1, although the expression profile almost overlaps with that of CRMP1 during development. These results suggest that CRMP complexes in the developing nervous system are classifiable into two populations that contain either CRMP1 or CRMP5. This indicates that different complexes may have distinct functions in shaping the neural networks.
CRMP（塌陷反应介导蛋白）家族被认为在神经发育过程中的生长锥导向中起关键作用。迄今为止鉴定出的四个成员（CRMP1 - 4）已被证明通过相互关联形成异源多聚体结构。在本研究中，我们通过酵母双杂交方法克隆了该家族的一个新成员，我们将其命名为CRMP5。该蛋白与其他CRMP成员的氨基酸同一性相对较低（49 - 50%），与二氢嘧啶酶的同一性也较低（51%），而CRMP1 - 4彼此之间的同一性较高（68 - 75%），这表明CRMP5可能被归类为第三个亚家族。小鼠CRMP5基因位于5号染色体B1区域。Northern印迹和原位杂交分析表明，CRMP5与其他成员（特别是CRMP1和CRMP4）类似，在整个神经系统中都有表达，在出生后第一周表达达到峰值。使用酵母双杂交方法和免疫共沉淀进行的关联实验表明，CRMP5与二氢嘧啶酶以及包括其自身在内的所有CRMP相互作用，但不与CRMP1相互作用，尽管在发育过程中其表达谱几乎与CRMP1的重叠。这些结果表明，发育中的神经系统中的CRMP复合物可分为含有CRMP1或CRMP5的两个群体。这表明不同的复合物在塑造神经网络中可能具有不同的功能。
