Development of cone photoreceptors and their synapses in the human and monkey fovea.
Development of cone photoreceptors and their synapses in the human and monkey fovea.
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DOI：
10.1002/cne.24170
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发表时间：
2019-01-01
期刊：
影响因子：
--
通讯作者：
Zhang C
中科院分区：
文献类型：
--
作者：
Hendrickson A;Zhang C
在视网膜发育过程中，光感受器中的带状突触组装是涉及众多分子的关键步骤。虽然人类视网膜丛状层的发育顺序已经被描述，但突触发生的分子步骤在很大程度上仍不清楚。在本研究中，我们聚焦于灵长类动物视网膜中央无杆区，即中央凹，专门研究视锥体光感受器带状突触的发育。应用免疫细胞化学和电子显微镜技术，追踪光感受器转导蛋白、条带和突触标志物在人胚胎和猕猴视网膜中的表达。虽然内丛状层比外丛状层出现得早，但突触蛋白和突触带在锥体蒂中首先被可靠地识别。短(S)和中/长(M/L)波长选择性视锥细胞表达突触标记的时间顺序相同，这与视蛋白的表达无关，视蛋白表达在S视锥细胞比M/L视锥细胞早一个月。突触前囊泡释放和突触后神经传导相关的带状标记物在胚胎第13周出现在两个丛层中。相比之下，锥体双极细胞谷氨酸能传递的两个关键成分代谢性谷氨酸受体6和电压依赖性钙通道α直到第22周才被检测到，此时双极细胞内陷在锥体蒂内。这些结果表明，在锥体突触发育过程中，分子有内在的程序性但不同步的表达。此外，功能性带状突触和中心凹锥体蒂的活跃神经传递可能早在妊娠中期就存在于人的视网膜中。
During retinal development, ribbon synapse assembly in the photoreceptors is a crucial step involving numerous molecules. While the developmental sequence of plexiform layers in human retina has been characterized, the molecular steps of synaptogenesis remain largely unknown. In the present study, we focused on the central rod-free region of primate retina, the fovea, to specifically investigate the development of cone photoreceptor ribbon synapses. Immunocytochemistry and electron microscopy were utilized to track the expression of photoreceptor transduction proteins and ribbon and synaptic markers in fetal human and Macaca retina. Although the inner plexiform layer appears earlier than the outer plexiform layer, synaptic proteins, and ribbons are first reliably recognized in cone pedicles. Markers first appear at fetal week 9. Both short (S) and medium/long (M/L) wavelength-selective cones express synaptic markers in the same temporal sequence; this is independent of opsin expression which takes place in S cones a month before M/L cones. The majority of ribbon markers, presynaptic vesicular release and postsynaptic neurotransduction-related machinery is present in both plexiform layers by fetal week 13. By contrast, two crucial components for cone to bipolar cell glutamatergic transmission, the metabotropic glutamate receptor 6 and voltage-dependent calcium channel α1.4, are not detected until fetal week 22 when bipolar cell invagination is present in the cone pedicle. These results suggest an intrinsically programmed but nonsynchronous expression of molecules in cone synaptic development. Moreover, functional ribbon synapses and active neurotransmission at foveal cone pedicles are possibly present as early as mid-gestation in human retina.
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产前人类视网膜视网膜层的发育。
影响因子：
4.2
作者：
Hendrickson A
通讯作者：
Hendrickson A
影响因子：
3.9
作者：
HENDRICKSON, A
通讯作者：
HENDRICKSON, A
影响因子：
4
作者：
CELIO, MR;BAIER, W;GERDAY, C
通讯作者：
GERDAY, C
影响因子：
4.2
作者：
Hendrickson, Anita;Possin, Daniel;Vajzovic, Lejla;Toth, Cynthia A.
通讯作者：
Toth, Cynthia A.
影响因子：
4.8
作者：
Cai, YF;Singh, BB;Ferreira, PA
通讯作者：
Ferreira, PA