Sullivan D T, Donovan F A, Skuse G
Biochem Genet. 1983 Feb;21(1-2):49-62. doi: 10.1007/BF02395391.
Methods have been developed to measure the synthesis of glycerol-3-phosphate dehydrogenase (GPDH) during the development of Drosophila melanogaster. In emerged adult flies, GPDH is a principal component of protein synthesis, comprising between 1 and 2% of the protein synthetic effort. This high relative rate of protein synthesis continues throughout adult life during a period of stable enzyme concentration. Therefore, it is evident that GPDH undergoes continual turnover. Analysis of GPDH synthesis in the adult segments reveals that this enzyme is synthesized in head, thorax, and abdomen. In 5-day-old flies, the relative rates of GPDH synthesis in the thorax and abdomen are similar. However, the concentration of GPDH in the thorax greatly exceeds that found in the abdomen. Therefore, it appears that the turnover rate of GPDH in the abdomen must be greater than the turnover rate of GPDH in the GPDH-containing cells (flight muscle) of the thorax. GPDH represents between 0.5 and 0.9% of the protein synthetic effort of larvae. The principle GPDH-containing tissue of larvae is fat body. The turnover of GPDH in larvae is similar to that in adult abdomen. This may be related to the concurrent presence of GPDH isozyme-3 in both tissues. Our studies indicate that the cell type-specific control of GPDH occurs at several levels.
已开发出方法来测量黑腹果蝇发育过程中甘油-3-磷酸脱氢酶（GPDH）的合成。在羽化后的成年果蝇中，GPDH是蛋白质合成的主要成分，占蛋白质合成量的1%至2%。在酶浓度稳定的成年期，这种较高的蛋白质合成相对速率会持续存在。因此，很明显GPDH会持续更新。对成年果蝇各体段中GPDH合成的分析表明，这种酶在头部、胸部和腹部均有合成。在5日龄的果蝇中，胸部和腹部GPDH的合成相对速率相似。然而，胸部GPDH的浓度大大超过腹部。因此，似乎腹部GPDH的更新速率必定大于胸部含GPDH细胞（飞行肌）中GPDH的更新速率。GPDH占幼虫蛋白质合成量的0.5%至0.9%。幼虫含GPDH的主要组织是脂肪体。幼虫中GPDH的更新与成年腹部相似。这可能与两种组织中同时存在GPDH同工酶-3有关。我们的研究表明，GPDH的细胞类型特异性控制发生在多个水平。
