Kim So Hee, Kim Hyeon Ju, Kim Soo Youn, Jeon Sang-Hak, Kim Sang Hee
Department of Chemistry, Konkuk University, Seoul, Korea.
Genesis. 2007 May;45(5):266-74. doi: 10.1002/dvg.20283.
Central nervous system (CNS) midline cells are essential for identity determination and differentiation of neurons in the Drosophila nervous system. It is not clear, however, whether CNS midline cells are also involved in the development of lateral glial cells. The roles of CNS midline cells in lateral glia development were elucidated using general markers for lateral glia, such as glial cell missing and reverse polarity, and specific enhancer trap lines labeling the longitudinal, A, B, medial cell body, peripheral, and exit glia. We found that CNS midline cells were necessary for the proper expression of glial cell missing, reverse polarity, and other lateral glia markers only during the later stages of development, suggesting that they are not required for initial identity determination. Instead, CNS midline cells appear to be necessary for proper division and survival of lateral glia. CNS midline cells were also required for proper positioning of three exit glia at the junction of segmental and intersegmental nerves, as well as some peripheral glia along motor and sensory axon pathways. This study demonstrated that CNS midline cells are extrinsically required for the proper division, migration, and survival of various classes of lateral glia from the ventral neuroectoderm.
中枢神经系统（CNS）中线细胞对于果蝇神经系统中神经元的身份确定和分化至关重要。然而，尚不清楚CNS中线细胞是否也参与外侧神经胶质细胞的发育。利用外侧神经胶质细胞的通用标记物，如胶质细胞缺失和反向极性，以及标记纵向、A、B、内侧细胞体、外周和出口神经胶质细胞的特定增强子捕获系，阐明了CNS中线细胞在外侧神经胶质细胞发育中的作用。我们发现，CNS中线细胞仅在发育后期才是胶质细胞缺失、反向极性和其他外侧神经胶质细胞标记物正常表达所必需的，这表明它们对于初始身份确定并非必需。相反，CNS中线细胞似乎是外侧神经胶质细胞正常分裂和存活所必需的。CNS中线细胞对于三个出口神经胶质细胞在节段神经和节间神经交界处的正确定位，以及沿运动和感觉轴突通路的一些外周神经胶质细胞的正确定位也是必需的。这项研究表明，CNS中线细胞对于来自腹侧神经外胚层的各类外侧神经胶质细胞的正常分裂、迁移和存活是外在必需的。
