Expression of the LIM-homeodomain protein IsI1 in the developing and mature mouse retina
Expression of the LIM-homeodomain protein IsI1 in the developing and mature mouse retina
复制标题
DOI：
10.1002/cne.21390
复制
发表时间：
2007-07-01
影响因子：
2.5
通讯作者：
Gan, Lin
中科院分区：
文献类型：
--
作者：
Elshatory, Yasser;Deng, Min;Gan, Lin
哺乳动物视网膜由六种主要的神经元细胞类型组成，并细分为更多的形态和生理亚型。这些亚型命运选择基础的转录机制在很大程度上是未知的。 Lim-Homeodomain蛋白ISL1在中枢神经系统（CNS）分化中起着至关重要的作用，但其与视网膜神经发生的关系仍然未知。我们在这里报告其在小鼠视网膜中的动态时空表达。在双极中间神经元中，ISL1表达在产后（P）5开始，后来仅限于双极细胞。发现ISL1表达的强度可将双极细胞的池分离为棒双极细胞，在杆双极细胞中表达较高。随着双极细胞的发育从P5-10进行，ISL1的共定位，泛极细胞标记CHX10揭示了中心双极细胞核的组织到内部核层的上部。此外，尽管ISL1主要是胚胎日（E）15.5之前的神经节细胞标记物，而在E15.5处，后来其在Nonganglion细胞中的表达却膨胀。我们证明，这些ISL1阳性，非甘道细胞会胚胎中获取无链氨氨酸细胞标记物的表达，可能代表新生的胆碱能无氨基氨酸细胞。综上所述，ISL1在成熟过程中表达，后来在视网膜神经节细胞和双极细胞的亚型中保持，在这些细胞和双极细胞的亚型中，它们可能在维持这些细胞成年的情况下起作用。
The mammalian retina is comprised of six major neuronal cell types and is subdivided into more morphological and physiological subtypes. The transcriptional machinery underlying these subtype fate choices is largely unknown. The LIM-homeodomain protein, Isl1, plays an essential role in central nervous system (CNS) differentiation but its relationship to retinal neurogenesis remains unknown. We report here its dynamic spatiotemporal expression in the mouse retina. Among bipolar interneurons, Isl1 expression commences at postnatal day (P)5 and is later restricted to ON-bipolar cells. The intensity of Isl1 expression is found to segregate the pool of ON-bipolar cells into rod and ON-cone bipolar cells with higher expression in rod bipolar cells. As bipolar cell development proceeds from P5-10 the colocalization of Isl1 and the pan-bipolar cell marker Chx10 reveals the organization of ON-center bipolar cell nuclei to the upper portion of the inner nuclear layer. Further, whereas Isl1 is predominantly a ganglion cell marker prior to embryonic day (E)15.5, at E15.5 and later its expression in nonganglion cells expands. We demonstrate that these Isl1-positive, nonganglion cells acquire the expression of amacrine cell markers embryonically, likely representing nascent cholinergic amacrine cells. Taken together, Isl1 is expressed during the maturation of and is later maintained in retinal ganglion cells and subtypes of amacrine and bipolar cells where it may function in the maintenance of these cells into adulthood.