The products of the Drosophila discs-large (dlg) gene are members of the MAGUK family of proteins, a group of proteins involved in localization, transport and recycling of receptors and channels in cell junctions, including the synapse. In vertebrates, four genes with multiple splice variants homologous to dlg are described. dlg originates two main proteins, DLGA, similar to the vertebrate neuronal protein PSD95, and DLGS97, similar to the vertebrate neuronal and epithelial protein SAP97. DLGA is expressed in epithelia, neural tissue and muscle. DLGS97 is expressed in neural tissue and muscle but not in epithelia. The distinctive difference between them is the presence in DLGS97 of an L27 domain. The differential expression between these variants makes the study of DLGS97 of key relevance to understand the in vivo role of synaptic MAGUKs in neurons. Here we present the temporal and spatial expression pattern of DLGS97 during embryonic and larval nervous system development, during eye development and in adult brain. Our results show that DLGS97 is expressed zygotically, in neurons in the embryo, larvae and adult, and is absent at all stages in glial cells. During eye development DLGS97 starts to be expressed in photoreceptor cells at early stages of differentiation and localizes basal to the basolateral junctions. In the brain, DLGS97 is expressed in the mushroom bodies and optic lobes at larval and adult stages; and in the antennal lobe in the adult stage. In addition we show that both, dlgS97 and dlgA transcripts, express during development multiple splice variants with differences in the use of exons in two sites.

中文翻译：

---

果蝇 DLGS97 在神经发育过程中的时空表达。

Drosophila discs-large (dlg) 基因的产物是 MAGUK 蛋白质家族的成员，MAGUK 家族是一组参与细胞连接（包括突触）中受体和通道的定位、运输和再循环的蛋白质。在脊椎动物中，描述了具有与 dlg 同源的多个剪接变体的四个基因。dlg 起源于两种主要蛋白质，DLGA，类似于脊椎动物神经元蛋白 PSD95，和 DLGS97，类似于脊椎动物神经元和上皮蛋白 SAP97。DLGA 在上皮、神经组织和肌肉中表达。DLGS97 在神经组织和肌肉中表达，但不在上皮细胞中表达。它们之间的显着区别在于 DLGS97 中存在 L27 域。这些变体之间的差异表达使得对 DLGS97 的研究对于了解突触 MAGUK 在神经元中的体内作用具有关键意义。在这里，我们展示了 DLGS97 在胚胎和幼虫神经系统发育、眼睛发育和成人大脑中的时空表达模式。我们的结果表明 DLGS97 在胚胎、幼虫和成虫的神经元中合子表达，并且在神经胶质细胞的所有阶段都不存在。在眼睛发育过程中，DLGS97 在分化的早期阶段开始在感光细胞中表达，并定位于基底外侧连接处。在大脑中，DLGS97在幼虫和成虫阶段的蘑菇体和视叶中表达；并在成年期的触角叶中。此外，我们表明 dlgS97 和 dlgA 转录本，