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氨基酰-tRNA合成酶(aminoacyl-tRNA synthetase,aa RS)负责催化氨基酸与对应的tRNA生成氨基酰-tRNA,参与蛋白质的生物合成。aaRS除可以活化其对应的氨基酸外,也可误活化一些与对应氨基酸相似的非对应氨基酸。基于此,aaRS进化出一种编校功能,可以水解误活化或误氨基酰化的氨基酸,保证翻译的正确进行。一旦某种特定的aaRS的编校功能受损,会导致非对应氨基酸误掺入蛋白质,引起蛋白质误折叠。细胞通过上调热休克蛋白来帮助误折叠蛋白质重折叠。误折叠的蛋白质可能会聚集,引起ER应激,或通过泛素化-蛋白酶体途径降解。若超过细胞修复功能所能承受的范围,细胞会凋亡,对于多细胞生物来说,可能会引起一系列疾病,而对于单细胞生物来说,生长会受到抑制,严重的会直接死亡。
Aminoacyl-tRNA synthetase (aa RS) is responsible for catalyzing amino acid and corresponding tRNA to generate aminoacyl-tRNA, which is involved in protein biosynthesis. In addition to activating their corresponding amino acids, aaRS may also inactivate some non-corresponding amino acids that are similar to the corresponding amino acids. Based on this, aaRS evolved a kind of editing function that could hydrolyze misactivated or mis-amino-acylated amino acids to ensure correct translation. Once a specific aaRS editing function is impaired, will lead to misclassified amino acids misclassified protein, causing protein misfolding. Cells help refolding misfolded proteins by up-regulating heat shock proteins. Misfolded proteins may aggregate, cause ER stress, or be degraded by the ubiquitination-proteasome pathway. If the cell repair function beyond the scope of the cells can be apoptosis, for the multi-cell organisms, may cause a series of diseases, and for single-cell organisms, growth will be suppressed, serious will die directly.