The rod cell has an extraordinarily specialized structure that allows it to carry out its unique function of detecting individual photons of light. Both the structural features of the rod and the metabolic processes required for highly amplified light detection seem to have rendered the rod especially sensitive to structural and metabolic defects, so that a large number of gene defects are primarily associated with rod cell death and give rise to blinding retinal dystrophies. The structures of the rod, especially those of the sensory cilium known as the outer segment, have been the subject of structural, biochemical, and genetic analysis for many years, but the molecular bases for rod morphogenesis and for cell death in rod dystrophies are still poorly understood. Recent developments in imaging technology, such as cryo-electron tomography and super-resolution fluorescence microscopy, in gene sequencing technology, and in gene editing technology are rapidly leading to new breakthroughs in our understanding of these questions. A summary is presented of our current understanding of selected aspects of these questions, highlighting areas of uncertainty and contention as well as recent discoveries that provide new insights. Examples of structural data from emerging imaging technologies are presented.

棒状细胞具有特殊的结构，可以执行检测单个光子的独特功能。杆的结构特征和高度放大的光检测所需的代谢过程似乎都使杆对结构和代谢缺陷特别​​敏感，因此大量的基因缺陷主要与杆细胞死亡有关，并导致杆状细胞死亡。致盲的视网膜营养不良。杆的结构，尤其是感觉纤毛的外段结构，已经成为结构，生化和遗传分析的主题，但对于杆形态发生和杆营养不良的细胞死亡的分子基础仍然存在知之甚少。成像技术的最新发展，在诸如基因测序技术和基因编辑技术等领域，如冷冻电子断层扫描和超分辨率荧光显微镜，正在迅速导致我们对这些问题的理解取得新的突破。总结了我们对这些问题某些方面的当前理解，重点介绍了不确定性和争论领域以及提供新见解的最新发现。给出了来自新兴成像技术的结构数据的示例。重点介绍不确定性和争论的领域，以及提供新见解的最新发现。给出了来自新兴成像技术的结构数据的示例。重点介绍不确定性和争论的领域，以及提供新见解的最新发现。给出了来自新兴成像技术的结构数据的示例。