The School of Public Health, Guangxi Medical University, Nanning, Guangxi, People's Republic of China.
Invest Ophthalmol Vis Sci. 2012 Mar 9;53(3):1162-8. doi: 10.1167/iovs.11-9262.
Biospectroscopy tools are increasingly being recognized as novel approaches toward interrogating complex biological structures in a nondestructive fashion. This study was conducted to apply these tools to interrogate alterations in the molecular signatures of developing chick corneas during the onset and development of transparency.
Embryonic chick corneas (n = 46) were obtained at 2-day intervals from embryonic day (E)10 to E18 of incubation and investigated with attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and Raman microspectroscopy. Resultant spectra were analyzed for variance by using principal component analysis and linear discriminant analysis (PCA-LDA).
Mean spectra after ATR-FTIR spectroscopy or Raman microspectroscopy derived from corneas at each developmental stage showed some overlap; however, in PCA-LDA scores plots, a clear segregation of spectra was evident, and two-category discrimination indicated that significant molecular alterations occur during tissue morphogenesis. Notable by both techniques was the increasing intensity of DNA signal (1080 cm⁻¹) from E10 onward. Major segregating biomarkers identified by ATR-FTIR spectroscopy between E10 and E18 were in the DNA/RNA (1126 cm⁻¹), glycogen (1045 cm⁻¹), protein (1470 cm⁻¹), and amide II (1512 cm⁻¹ and 1524 cm⁻¹) spectral regions. Raman spectroscopy also identified major distinguishing vibrational modes that included proteins, amino acids (tyrosine, proline phenylalanine, and valine), and secondary structures of proteins (amide I and amide II).
The developing chick cornea undergoes significant changes in its biomolecular composition in the E10 to E18 developmental period, with the major changes occurring in the spectral regions associated with DNA/RNA, proteins, glycogen, and secondary protein structures.
生物光谱学工具正逐渐被视为一种非破坏性的方法，用于探究复杂生物结构的新方法。本研究旨在应用这些工具来研究胚胎鸡角膜在透明性发生和发育过程中分子特征的变化。
从孵化的胚胎第 10 天（E10）到第 18 天（E18），每隔 2 天获取胚胎鸡角膜（n = 46），并用衰减全反射傅里叶变换红外（ATR-FTIR）光谱和拉曼微光谱进行研究。用主成分分析和线性判别分析（PCA-LDA）对所得光谱进行方差分析。
ATR-FTIR 光谱或拉曼微光谱从每个发育阶段的角膜获得的平均光谱存在一定程度的重叠；然而，在 PCA-LDA 得分图中，光谱明显分离，两类判别表明组织形态发生过程中存在显著的分子变化。两种技术都可以检测到 DNA 信号（1080 cm⁻¹）从 E10 开始增强。ATR-FTIR 光谱在 E10 至 E18 之间鉴定的主要分离生物标志物位于 DNA/RNA（1126 cm⁻¹）、糖原（1045 cm⁻¹）、蛋白质（1470 cm⁻¹）和酰胺 II（1512 cm⁻¹ 和 1524 cm⁻¹）光谱区域。拉曼光谱也确定了主要的区别振动模式，包括蛋白质、氨基酸（酪氨酸、脯氨酸、苯丙氨酸和缬氨酸）和蛋白质的二级结构（酰胺 I 和酰胺 II）。
E10 至 E18 发育期间，鸡角膜的生物分子组成发生了显著变化，主要变化发生在与 DNA/RNA、蛋白质、糖原和二级蛋白质结构相关的光谱区域。
