The proteasome activator 11 S REG or PA28: chimeras implicate carboxyl-terminal sequences in oligomerization and proteasome binding but not in the activation of specific proteasome catalytic subunits.
The proteasome activator 11 S REG or PA28: chimeras implicate carboxyl-terminal sequences in oligomerization and proteasome binding but not in the activation of specific proteasome catalytic subunits.
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蛋白酶体激活剂 11 S REG 或 PA28：嵌合体暗示羧基末端序列参与寡聚化和蛋白酶体结合，但不参与特定蛋白酶体催化亚基的激活。
DOI：
10.1006/jmbi.2000.3800
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Rechsteiner,M
中科院分区：
文献类型：
--
作者：
Li,J;Gao,X;Joss,L;Rechsteiner,M
REG同系物α、β和γ以不同的方式激活哺乳动物蛋白酶体。REGα和REGβ激活胰蛋白酶样、胰凝乳蛋白酶样和肽酰谷氨酰偏好活性位点，而REGγ仅激活蛋白酶体的胰蛋白酶样亚基。这三种REG同源物的羧基末端序列不同，羧基末端序列位于其蛋白酶体结合表面上的激活环旁边。为了评估这些羧基末端序列在特定蛋白酶体β催化亚基活化中的重要性，我们表征了三种蛋白质之间交换8或12个残基的嵌合体。与野生型分子一样，REGα嵌合体激活了所有三个蛋白酶体催化亚基，而不管羧基末端序列如何。然而，REGα-β嵌合体在比野生型REGα更低的浓度下激活蛋白酶体，并且需要更高水平的REGα-γ嵌合体以实现最大激活，因为交换的羧基末端序列可以稳定（REGα-β）或不稳定（REGα-γ）REGα七聚体。REGγ嵌合体在激活特性上与REGγ相当，但它们与蛋白酶体的结合不如野生型分子紧密。REGβ嵌合体与蛋白酶体的结合也比野生型REGβ弱，实际上不能激活它。我们的研究结果表明，REG亚基的羧基末端序列可以影响七聚体的稳定性和蛋白酶体亲和力，但它们不能决定哪些蛋白酶体β亚基被激活。
The REG homologs, α, β and γ, activate mammalian proteasomes in distinct ways. REGα and REGβ activate the trypsin-like, chymotrypsin-like and peptidylglutamyl-preferring active sites, whereas REGγ only activates the proteasome’s trypsin-like subunit. The three REG homologs differ in carboxyl-terminal sequences that are located next to activation loops on their proteasome binding surface. To assess the importance of these carboxyl-terminal sequences in the activation of specific proteasome β catalytic subunits, we characterized chimeras in which 8 or 12 residues were exchanged among the three proteins. Like the wild-type molecule, REGα chimeras activated all three proteasome catalytic subunits regardless of the carboxyl-terminal sequence. However, REGα-β chimeras activated the proteasome at lower concentrations than wild-type REGα and higher levels of REGα-γ chimeras were needed for maximal activation because exchanged carboxyl-terminal sequences can stabilize (REGα-β) or destabilize (REGα-γ) the REGα heptamer. REGγ chimeras were equivalent to REGγ in their activation properties, but they bound the proteasome less tightly than the wild-type molecule. REGβ chimeras also bound the proteasome more weakly than wild-type REGβ and were virtually unable to activate it. Our findings demonstrate that the carboxyl-terminal sequences of REG subunits can affect heptamer stability and proteasome affinity, but they do not determine which proteasome β subunits become activated.
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DOI：
10.1016/s0006-291x(87)80261-9
发表时间：
1987-11-13
影响因子：
3.1
作者：
GRINO, M;CHROUSOS, GP;MARGIORIS, AN
通讯作者：
MARGIORIS, AN
正常妊娠血浆肾素、肾素底物、血管紧张素II、醛固酮和电解质之间的关系。
DOI：
10.1210/jcem-40-1-108
发表时间：
1975
期刊：
The Journal of clinical endocrinology and metabolism
影响因子：
--
作者：
R. Weir;J. J. Brown;R. Fraser;A. Lever;R. W. Logan;G. McIlwaine;J. Morton;J. Robertson;M. Tree
通讯作者：
M. Tree
影响因子：
56.9
作者：
SAPOLSKY, R;RIVIER, C;VALE, W
通讯作者：
VALE, W
人胎儿垂体中促肾上腺皮质激素的促垂体和神经调节调节。
DOI：
10.1172/jci112563
发表时间：
1986
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
Blumenfeld,Z;Jaffe,RB
通讯作者：
Jaffe,RB
DOI：
10.1210/jcem-55-2-384
发表时间：
1982-08
期刊：
The Journal of clinical endocrinology and metabolism
影响因子：
--
作者：
T. Shibasaki;E. Odagiri;K. Shizume;N. Ling
通讯作者：
T. Shibasaki;E. Odagiri;K. Shizume;N. Ling