Dendritic stratification differs among retinal OFF bipolar cell types in the absence of rod photoreceptors.
Dendritic stratification differs among retinal OFF bipolar cell types in the absence of rod photoreceptors.
复制标题
DOI：
10.1371/journal.pone.0173455
复制
发表时间：
2017
期刊：
影响因子：
3.7
通讯作者：
Haverkamp S
中科院分区：
文献类型：
--
作者：
Puller C;Arbogast P;Keeley PW;Reese BE;Haverkamp S
在野生型小鼠视网膜中，视网膜OFF双极细胞与光感受器显示出不同的连接模式。一些类型是视锥细胞特异性的，而另一些类型则进一步穿透外网状层（OPL），除了视锥细胞外还与视杆细胞接触。为了探索在不存在视杆细胞的情况下OFF双极细胞的树突分层，我们利用了“全视锥”Nrl-/-小鼠视网膜，其中所有光感受器前体细胞都致力于视锥命运，包括那些在野生型视网膜中会变成视杆细胞的细胞。通过免疫标记组织切片的共聚焦和电子显微镜成像研究OFF双极细胞类型的树突状分布。这些细胞的树突与视锥末梢形成基底接触，并在这些部位表达相应的谷氨酸受体亚单位，表明假定的突触。所有的四个分析的细胞群体表现出独特的模式垂直树突状细胞入侵通过OPL。这种不同的行为树突状细胞的延伸在一个环境中只含有锥终端证明了类型依赖性的特异性树突状细胞生长在OFF双极细胞：杆终端不需要诱导树突状细胞延伸到远端地区的OPL。
Retinal OFF bipolar cells show distinct connectivity patterns with photoreceptors in the wild-type mouse retina. Some types are cone-specific while others penetrate further through the outer plexiform layer (OPL) to contact rods in addition to cones. To explore dendritic stratification of OFF bipolar cells in the absence of rods, we made use of the ‘cone-full’ Nrl-/- mouse retina in which all photoreceptor precursor cells commit to a cone fate including those which would have become rods in wild-type retinas. The dendritic distribution of OFF bipolar cell types was investigated by confocal and electron microscopic imaging of immunolabeled tissue sections. The cells’ dendrites formed basal contacts with cone terminals and expressed the corresponding glutamate receptor subunits at those sites, indicating putative synapses. All of the four analyzed cell populations showed distinctive patterns of vertical dendritic invasion through the OPL. This disparate behavior of dendritic extension in an environment containing only cone terminals demonstrates type-dependent specificity for dendritic outgrowth in OFF bipolar cells: rod terminals are not required for inducing dendritic extension into distal areas of the OPL.