McFall-Ngai M J, Ding L L, Takemoto L J, Horwitz J
Exp Eye Res. 1985 Dec;41(6):745-58. doi: 10.1016/0014-4835(85)90183-6.
Using the techniques of high performance liquid chromatography (HPLC), gel electrophoresis in the presence of sodium dodecyl sulfate (SDS), and immunoblotting, we have analyzed the age-related changes in soluble crystallins of the human lens. A 3 mm core along the optical axis of each lens was frozen-sectioned and the sections were biochemically analyzed for distribution and quantity of the various soluble protein species. Both cortical and nuclear samples show a monotonic decrease in the concentration of the 19 000 and 21 000 MW proteins with age. We find that these proteins behave anomalously on SDS-polyacrylamide gels, running near the top of the gel when the samples are not boiled before loading; this permitted us to observe the gradual, age-related loss of these bands from the gels of both nuclear and cortical samples. The high molecular weight, or TSK-3000 void volume, fraction (greater than 350,000) of the cortex contained alpha crystallin at all ages. However, in the nucleus, while this fraction is primarily composed of alpha crystallin early in life (i.e. before 15 years of age), there is a gradual incorporation of other crystallins into the void volume. This change in the composition of the high-molecular-weight, soluble protein fraction is reflected in: a change in the subunit mobility on SDS-polyacrylamide gels; reactivity of the fraction to crystallin antibodies, i.e. in the young nucleus there is reactivity to anti-alpha crystallin only, with a gradual increase in reactivity to anti-beta and anti-gamma crystallins. The void volume fraction of the nucleus persists as a major component of the soluble protein pool until 42-44 years of age, at which time the proportion of the total soluble protein represented by this void volume fraction decreases precipitously. These changes in the soluble protein profile are discussed in terms of their potential influence on the functioning of the lens.
运用高效液相色谱（HPLC）技术、十二烷基硫酸钠（SDS）存在下的凝胶电泳技术以及免疫印迹法，我们分析了人晶状体可溶性晶状体蛋白的年龄相关性变化。沿着每个晶状体光轴取3毫米的核心进行冷冻切片，并对切片进行生物化学分析，以确定各种可溶性蛋白质种类的分布和数量。皮质和核样本均显示，随着年龄增长，19000和21000分子量蛋白质的浓度呈单调下降。我们发现，这些蛋白质在SDS - 聚丙烯酰胺凝胶上表现异常，当样品在上样前未煮沸时，它们会在凝胶顶部附近迁移；这使我们能够观察到核样本和皮质样本凝胶中这些条带随年龄逐渐消失的情况。皮质的高分子量或TSK - 3000空隙体积部分（大于350,000）在所有年龄段都含有α晶状体蛋白。然而，在核中，虽然该部分在生命早期（即15岁之前）主要由α晶状体蛋白组成，但其他晶状体蛋白会逐渐掺入空隙体积中。高分子量可溶性蛋白质部分组成的这种变化反映在：SDS - 聚丙烯酰胺凝胶上亚基迁移率的变化；该部分与晶状体蛋白抗体的反应性，即在年轻的核中仅与抗α晶状体蛋白有反应，而与抗β和抗γ晶状体蛋白的反应性逐渐增加。核的空隙体积部分一直是可溶性蛋白质池的主要成分，直到42 - 44岁，此时该空隙体积部分占总可溶性蛋白质的比例急剧下降。本文根据这些变化对晶状体功能的潜在影响进行了讨论。
