葡萄糖调节蛋白GRP78和GRP94在小鼠脑发育过程中的差异表达

为探讨葡萄糖调节蛋白GRP78和GRP94在小鼠脑发育过程中的生物学意义,利用蛋白质免疫印迹、免疫荧光及RNA印迹技术,检测了发育不同时期小鼠脑组织中GRP78、GRP94的表达及分布情况.结果显示:小鼠脑发育过程中GRP78、GRP94的表达在时间和空间上呈现出显著差异,在脑发育的早中期GRP78表达水平高于GRP94,随发育的进程GRP78不断下降而GRP94逐渐升高,至胚胎发育晚期GRP94表达水平高于GRP78.在E16.5的不同脑区,GRP78的表达呈现出从端脑到后脑逐渐递减的“浓度梯度”分布,而GRP94在不同脑区中表达相同.小鼠出生后,二者作为应激蛋白在脑组织中的表达没有明显的差异性.免疫荧光结果显示,GRP78和GRP94在大脑组织中的分布基本相同,神经细胞和神经胶质细胞的细胞质均有分布.这些观察得到的结果提示,GRP78和GRP94与神经细胞分化和脑的形态建成有关,它们分别在脑发育的不同时期起作用.

The Differential Expression of Glucose Regulated Proteins (GRP78 and GRP94) in Brain During Mouse Development

To investigate the effects of glucose regulated proteins (GRP78 and GRP94) on brain development, the expression of GRP78 and GRP94 in brain during mouse development were examined by Western blot, Northern blot and immunofluorescence. The results showed that the GRP78 and GRP94 proteins were expressed in the different spatio-temporal patterns during brain development. The level of GRP78 was higher than GRP94 in embryonic brain during the early stages of organogenesis, and gradually decreased at the later fetal stages. In contrast, the level of GRP94 was gradually increasing and exceeded the level of GRP78 at later fetal stages. Furthermore, the level of GRP78 was gradually decreasing from telencephalon to hindbrain on E16.5 but GRP94 was not. As stress proteins, the levels of GRP78 and GRP94 in brain were similar during postnatal development of mouse. In addition, the distribution of GRP78 in brain was in agreement with GRP94, which was localized within the neurons and glial cells. These results suggested that GRP78 and GRP94 played the different roles in the process of nerve cell differentiation and brain morphogenesis. They had distinct functions in the different stages during brain development of mouse.