Hawse John R, DeAmicis-Tress Candida, Cowell Tracy L, Kantorow Marc
Department of Biomedical Science, Florida Atlantic University, Boca Raton, FL, USA.
Mol Vis. 2005 Apr 18;11:274-83.
In order to identify specific genes that may play important roles in maintaining the specialized functions of lens epithelial and fiber cells, we have analyzed the global gene expression profiles of these two cell types in the human lens. This analysis will also reveal those genes that are exclusively expressed in the epithelial and cortical fiber cells and those genes that may play important roles in the differentiation of epithelial cells to mature fiber cells.
Oligonucleotide microarray hybridization was used to analyze the expression profiles of 22,215 genes between adult (average age greater than 56 years) human lens epithelial and cortical fiber cells. The expression levels of selected genes were further compared by semi-quantitative RT-PCR and selected genes were functionally clustered into common categories using the EASE bioinformatics software package.
Analysis of three separate microarray hybridizations revealed 1,196 transcripts that exhibit increased expression and 1,278 transcripts that exhibit decreased expression at the 2 fold or greater level between lens epithelial cells and cortical fiber cells on all three of the arrays analyzed. Of these, 222 transcripts exhibited increased expression and 135 transcripts exhibited decreased expression by an average of 5 fold or greater levels on all three arrays. Semi-quantitative RT-PCR analysis of 21 randomly selected genes revealed identical expression patterns as those detected by microarray hybridization indicating that the microarray data are accurate. Functional clustering of the identified gene expression patterns using the EASE program revealed a wide variety of biological pathways that exhibited altered expression patterns between the two cell types including mRNA processing, cell adhesion, cell proliferation, translation, protein folding, oxidative phosphorylation, and apoptosis, among others.
These data reveal novel and previously identified gene expression differences between lens epithelial and cortical fiber cells. The gene expression differences indicate distinct pathways and functions important for the specialization of lens epithelial and fiber cells and provide insight into potential mechanisms important for lens cell differentiation.
为了鉴定可能在维持晶状体上皮细胞和纤维细胞特殊功能中发挥重要作用的特定基因，我们分析了人晶状体中这两种细胞类型的整体基因表达谱。该分析还将揭示那些仅在上皮细胞和皮质纤维细胞中表达的基因，以及那些可能在从上皮细胞分化为成熟纤维细胞过程中发挥重要作用的基因。
使用寡核苷酸微阵列杂交技术分析成年（平均年龄大于56岁）人晶状体上皮细胞和皮质纤维细胞之间22215个基因的表达谱。通过半定量逆转录聚合酶链反应（RT-PCR）进一步比较所选基因的表达水平，并使用EASE生物信息学软件包将所选基因功能聚类为常见类别。
对三次独立的微阵列杂交分析显示，在所有三个分析阵列上，晶状体上皮细胞和皮质纤维细胞之间有1196个转录本表达增加，1278个转录本表达降低，且变化倍数在2倍或更高水平。其中，在所有三个阵列上，222个转录本表达增加，135个转录本表达降低，平均变化倍数为5倍或更高。对21个随机选择的基因进行半定量RT-PCR分析，结果显示与微阵列杂交检测到的表达模式相同，表明微阵列数据准确。使用EASE程序对鉴定出的基因表达模式进行功能聚类，结果显示在这两种细胞类型之间存在多种表达模式改变的生物学途径，包括mRNA加工、细胞黏附、细胞增殖、翻译、蛋白质折叠、氧化磷酸化和细胞凋亡等。
这些数据揭示了晶状体上皮细胞和皮质纤维细胞之间新的以及先前已确定的基因表达差异。这些基因表达差异表明了对晶状体上皮细胞和纤维细胞特化重要的不同途径和功能，并为晶状体细胞分化的潜在重要机制提供了见解。
