Lens Biology and Biochemistry.
Lens Biology and Biochemistry.
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DOI：
10.1016/bs.pmbts.2015.04.007
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发表时间：
2015
影响因子：
--
通讯作者：
Shiels A
中科院分区：
文献类型：
--
作者：
Hejtmancik JF;Riazuddin SA;McGreal R;Liu W;Cvekl A;Shiels A
透镜的主要功能在于其透明度和将光聚焦在视网膜上的能力。这些要求透镜细胞含有高浓度的密集堆积的透镜晶体蛋白以在接近待透射的光的波长的距离上保持折射率恒定，以及在细胞核中缺乏细胞器的前上皮细胞和弓形纤维细胞的特定排列以避免阻挡光的透射。因为透镜核中的细胞已经脱落了它们的细胞器，所以透镜晶体蛋白必须持续生物体的寿命，并且特别适应于这种功能。透镜晶体蛋白包括两个主要家族：βγ-晶体蛋白是已知最稳定的蛋白质之一，α-晶体蛋白具有分子伴侣样功能。透镜的其他蛋白质和代谢活性主要被组织以保护晶状体蛋白免受随时间的损伤并维持透镜细胞的稳态。膜蛋白通道维持透镜的渗透和离子平衡，而透镜细胞骨架提供了透镜细胞的特定形状，特别是核的纤维细胞。也许最重要的是，透镜中的大部分代谢活动是针对维持还原状态，其保护透镜晶体蛋白和其它细胞组分免受UV光和氧化应激的损害。最后，透镜的能量需求主要通过糖酵解和戊糖磷酸途径来满足，这可能是对透镜的无血管性质的响应。所有这些系统一起协作以随时间保持透镜透明度。
The primary function of the lens resides in its transparency and ability to focus light on the retina. These require both that the lens cells contain high concentrations of densely packed lens crystallins to maintain a refractive index constant over distances approximating the wavelength of the light to be transmitted, and a specific arrangement of anterior epithelial cells and arcuate fiber cells lacking organelles in the nucleus to avoid blocking transmission of light. Because cells in the lens nucleus have shed their organelles, lens crystallins have to last for the lifetime of the organism, and are specifically adapted to this function. The lens crystallins comprise two major families: the βγ-crystallins are among the most stable proteins known and the α-crystallins, which have a chaperone-like function. Other proteins and metabolic activities of the lens are primarily organized to protect the crystallins from damage over time and to maintain homeostasis of the lens cells. Membrane protein channels maintain osmotic and ionic balance across the lens, while the lens cytoskeleton provides for the specific shape of the lens cells, especially the fiber cells of the nucleus. Perhaps most importantly, a large part of the metabolic activity in the lens is directed toward maintaining a reduced state, which shelters the lens crystallins and other cellular components from damage from UV light and oxidative stress. Finally, the energy requirements of the lens are met largely by glycolysis and the pentose phosphate pathway, perhaps in response to the avascular nature of the lens. Together, all these systems cooperate to maintain lens transparency over time.
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影响因子：
3.5
作者：
AUGUSTEYN, RC;KORETZ, JF
通讯作者：
KORETZ, JF
影响因子：
4
作者：
Bagchi, M;Katar, M;Maisel, H
通讯作者：
Maisel, H
影响因子：
5.6
作者：
Aravind, Penmatsa;Suman, Shashi Kumar;Sankaranarayanan, Rajan
通讯作者：
Sankaranarayanan, Rajan
影响因子：
2.9
作者：
Annunziata, O;Pande, A;Benedek, GB
通讯作者：
Benedek, GB
DOI：
10.1016/0006-291x(87)91634-2
发表时间：
1987-11-30
影响因子：
3.1
作者：
ALLEN, DP;LOW, PS;MAISEL, H
通讯作者：
MAISEL, H