Save Sight Institute and Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.
J Comp Neurol. 2024 Aug;532(8):e25663. doi: 10.1002/cne.25663.
The transcription factor forkhead/winged-helix domain proteins Foxp1 and Foxp2 have previously been studied in mouse retina, where they are expressed in retinal ganglion cells named F-mini and F-midi. Here we show that both transcription factors are expressed by small subpopulations (on average less than 10%) of retinal ganglion cells in the retina of the marmoset monkey (Callithrix jacchus). The morphology of Foxp1- and Foxp2-expressing cells was revealed by intracellular DiI injections of immunofluorescent cells. Foxp1- and Foxp2-expressing cells comprised multiple types of wide-field ganglion cells, including broad thorny cells, narrow thorny cells, and tufted cells. The large majority of Foxp2-expressing cells were identified as tufted cells. Tufted cells stratify broadly in the middle of the inner plexiform layer. They resemble broad thorny cells but their proximal dendrites are bare of branches and the distal dendrites branch frequently forming dense dendritic tufts. Double labeling with calretinin, a previously established marker for broad thorny and narrow thorny cells, showed that only a small proportion of ganglion cells co-expressed calretinin and Foxp1 or Foxp2 supporting the idea that the two markers are differentially expressed in retinal ganglion cells of marmoset retina.
叉头框/翼状螺旋转录因子 Foxp1 和 Foxp2 先前在小鼠视网膜中进行了研究，在那里它们在称为 F-mini 和 F-midi 的视网膜神经节细胞中表达。在这里，我们表明这两种转录因子都由狨猴（Callithrix jacchus）视网膜中的小亚群（平均不到 10%）的视网膜神经节细胞表达。通过对免疫荧光细胞进行细胞内 DiI 注射揭示了 Foxp1 和 Foxp2 表达细胞的形态。Foxp1 和 Foxp2 表达细胞包括多种宽场神经节细胞，包括宽棘细胞、窄棘细胞和丛状细胞。大多数 Foxp2 表达细胞被鉴定为丛状细胞。丛状细胞在内部神经丛层的中间广泛分层。它们类似于宽棘细胞，但它们的近端树突没有分支，而远端树突经常分支形成密集的树突丛。与 calretinin（先前用于鉴定宽棘细胞和窄棘细胞的标记物）的双重标记显示，只有一小部分神经节细胞共表达 calretinin 和 Foxp1 或 Foxp2，这支持了这两个标记物在狨猴视网膜神经节细胞中差异表达的观点。
