The effect of nutrient deprivation on proteasome activity in 4-week-old mice and 24-week-old mice
The effect of nutrient deprivation on proteasome activity in 4-week-old mice and 24-week-old mice
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营养剥夺对4周龄和24周龄小鼠蛋白酶体活性的影响
DOI：
10.1016/j.jnutbio.2022.108993
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发表时间：
2022
影响因子：
5.6
通讯作者：
and Keiji Tanaka
中科院分区：
文献类型：
--
作者：
Nobuyuki Tanahashi;Moeko Komiyama;Mina Tanaka;Yuta Yokobori Shigeo Murata;and Keiji Tanaka
最近，我们已经开始更好地了解蛋白酶体活性响应营养状态的调节机制。在这项研究中，我们分析了蛋白酶体在肝脏和大脑中的表达和功能，在短期饥饿期间，代谢系统发生变化。在4周龄小鼠的肝脏中，蛋白酶体活性随着禁食时间的推移而下降，而大脑蛋白酶体活性在禁食24小时后保持不变，然后下降。然而，24周龄小鼠的肝脏和大脑蛋白酶体活性下降，禁食24小时，然后恢复。无论年龄大小，组成肝脏和大脑中蛋白酶体的亚基的表达水平没有显着变化，形成的蛋白酶体的分子大小也没有变化。有趣的是，蛋白酶体组装蛋白Ump1随着蛋白酶体活性的变化而积累。当禁食状态恢复到进食状态时，脑中的蛋白酶体活性恢复到与进食状态几乎相同的水平，但肝脏中的蛋白酶体活性没有恢复到进食状态。在这种状态下，组装蛋白Ump1继续积累。这些结果表明：（1）Ump 1的表达受营养状态的控制，（2）蛋白酶体的形成机制可能因器官而异。
Recently, we have begun to better understand the regulatory mechanisms of proteasome activity in response to the nutritional state. In this study, we analyzed the expression and function of proteasomes in the livers and brains where changes in the metabolic system occurin vivoduring short-term starvation. In the livers of 4-week-old mice, proteasome activity decreased with fasting time, whereas brain proteasome activity remained unchanged by up to 24 h of fasting and then decreased. However, liver and brain proteasome activity in 24-week-old mice decreased by fasting for 24 h and then recovered. There was no significant change in the expression levels of the subunits that make up the proteasomes in livers and brains regardless of age, and there was no change in the molecular size of the formed proteasome. Interestingly, Ump1, a proteasome assembly protein, accumulated with changes in proteasome activity. When the fasted state returned to a fed state, the proteasome activity in the brain was restored to almost the same level as in the fed state, but the proteasome activity in the liver was not restored to that of the fed state. In this state, the assembly protein Ump1 continued to accumulate. These findings suggest that (1) the expression of Ump1 is controlled by the nutritional state, and (2) the proteasome formation mechanism may differ depending on the organ.