Gibson M C, Schubiger G
Department of Zoology, University of Washington, Seattle 98195, USA.
Cell. 2000 Oct 13;103(2):343-50. doi: 10.1016/s0092-8674(00)00125-2.
Cells employ a diverse array of signaling mechanisms to establish spatial patterns during development. Nowhere is this better understood than in Drosophila, where the limbs and eyes arise from discrete epithelial sacs called imaginal discs. Molecular-genetic analyses of pattern formation have generally treated discs as single epithelial sheets. Anatomically, however, discs comprise a columnar cell monolayer covered by a squamous epithelium known as the peripodial membrane. Here we demonstrate that during development, peripodial cells signal to disc columnar cells via microtubule-based apical extensions. Ablation and targeted gene misexpression experiments demonstrate that peripodial cell signaling contributes to growth control and pattern formation in the eye and wing primordia. These findings challenge the traditional view of discs as monolayers and provide foundational evidence for peripodial cell function in Drosophila appendage development.
在发育过程中，细胞利用多种信号传导机制来建立空间模式。这一点在果蝇中体现得最为明显，果蝇的肢体和眼睛源自称为成虫盘的离散上皮囊。模式形成的分子遗传学分析通常将成虫盘视为单一上皮片层。然而，从解剖学角度来看，成虫盘由柱状细胞单层组成，其表面覆盖着一层鳞状上皮，即围食膜。我们在此证明，在发育过程中，围食膜细胞通过基于微管的顶端延伸向盘柱状细胞发出信号。消融和靶向基因错误表达实验表明，围食膜细胞信号传导有助于眼睛和翅原基的生长控制和模式形成。这些发现挑战了将成虫盘视为单层的传统观点，并为围食膜细胞在果蝇附肢发育中的功能提供了基础证据。
