第1052回生物科学セミナー
Growth control in dendrites: lessons from Drosophila.
Jay Z. Parrish教授（Dep. of Biol., Univ. of Washington）
2015年07月13日(月) 13：30-14：30 理学部2号館 講堂
Neurons exhibit enormous diversity in form and size even in a single animal. Likewise, dendrite arbor size scales with increased body size for many types of neurons across phylogeny, thus neurons in larger animals must support greater growth demands. However, whether neurons with extreme growth requirements have specialized machinery to support their growth demands remains unknown. To address this question, we conducted a genetic screen for mutations that differentially affected growth in Drosophila sensory neurons with different sized dendrite arbors. From this screen, we identified a mutant, pathetic, that disrupts a putative amino acid transporter that localizes to the cell surface and endolysosomal compartments in neurons. Mutations in pathetic selectively affect dendrite growth in neurons with large dendrite arbors without affecting dendrite growth in neurons with small dendrite arbors or the animal overall, suggesting that pathetic defines a program required for extreme growth in neurons. Although Pathetic is broadly expressed in neurons and non-neuronal cells, mutation of path impinges on nutrient responses and protein homeostasis specifically in neurons with large dendrite arbors, but not in other cells. Altogether, our results demonstrate that specialized molecular mechanisms exist to support growth demands in neurons with large dendrite arbors and define Pathetic as a founding member of this growth program.
＜参考文献＞
1.Lin et al. The SLC36 transporter Pathetic is required for extreme dendrite growth in Drosophila sensory neurons. Genes Dev. 29: 1120-1135 (2015).
2.Jiang et al. The microRNA bantam regulates a developmental transition in epithelial cells that restricts sensory dendrite growth. Development 141: 2657-68 (2014).
3.Parrish et al. Krüppel mediates the selective rebalancing of ion channel expression. Neuron 82: 537-44 (2014).
