Cone Phosphodiesterase-6γ' Subunit Augments Cone PDE6 Holoenzyme Assembly and Stability in a Mouse Model Lacking Both Rod and Cone PDE6 Catalytic Subunits.
Cone Phosphodiesterase-6γ' Subunit Augments Cone PDE6 Holoenzyme Assembly and Stability in a Mouse Model Lacking Both Rod and Cone PDE6 Catalytic Subunits.
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DOI：
10.3389/fnmol.2018.00233
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发表时间：
2018
影响因子：
4.8
通讯作者：
Hauswirth WW
中科院分区：
文献类型：
--
作者：
Deng WT;Kolandaivelu S;Dinculescu A;Li J;Zhu P;Chiodo VA;Ramamurthy V;Hauswirth WW
视杆细胞和视锥细胞磷酸二酯酶6（Rod and cone phosphodiesterase 6，PDE 6）是脊椎动物光信号转导途径中的关键效应酶。视杆细胞PDE 6由两个催化亚基PDE 6 α和PDE 6 β以及两个相同的抑制性PDE 6 γ亚基组成，而视锥细胞PDE 6由两个相同的PDE 6 α'催化亚基和两个相同的视锥细胞特异性PDE 6 γ'抑制亚基组成。尽管它们在调节cGMP水平以及因此调节视杆细胞和视锥细胞光响应特性方面具有突出的功能，但尚不清楚每个亚基如何促成视杆细胞和视锥细胞之间的功能差异。在这项研究中，我们建立了一个rd 10/cpfl 1小鼠模型，缺乏杆PDE 6 β和锥PDE 6 α'亚基。视杆细胞和视锥细胞都随着年龄的增长而退化，并且所有PDE 6亚基在rd 10/cpfl 1小鼠中降解。我们通过腺相关病毒（AAV）介导的传递在rd 10/cpfl 1小鼠的视杆细胞和视锥细胞中表达锥型PDE 6 α'，该传递由无处不在的组成型小鸡β-肌动蛋白启动子驱动。我们发现，PDE 6 α'的表达挽救了rd 10/cpfl 1小鼠的视杆细胞功能，视杆细胞光敏感性的恢复是通过内源性视杆细胞PDE 6 γ的恢复和功能性PDE 6 γ'复合物的形成来实现的。然而，改善的明视锥反应仅在补充锥PDE 6 α'和PDE 6 γ'亚基后实现，而不是通过单独的PDE 6 α'处理。我们观察到，相对于仅接受PDE 6 α'的眼睛，注射PDE 6 α'和PDE 6 γ'的眼睛中PDE 6 α'水平增加了两倍。尽管存在PDE 6 γ'和PDE 6 γ，但大多数PDE 6 α'与PDE 6 β '形成功能性复合物，表明PDE 6 α'对PDE 6 γ'的缔合亲和力高于对PDE 6 γ的缔合亲和力。这些结果表明，PDE 6 γ'的存在增强了锥体PDE 6组装并提高了其稳定性。我们的发现对PDE 6 β '相关色盲的基因治疗具有重要意义。
Rod and cone phosphodiesterase 6 (PDE6) are key effector enzymes of the vertebrate phototransduction pathway. Rod PDE6 consists of two catalytic subunits PDE6α and PDE6β and two identical inhibitory PDE6γ subunits, while cone PDE6 is composed of two identical PDE6α’ catalytic subunits and two identical cone-specific PDE6γ’ inhibitory subunits. Despite their prominent function in regulating cGMP levels and therefore rod and cone light response properties, it is not known how each subunit contributes to the functional differences between rods and cones. In this study, we generated an rd10/cpfl1 mouse model lacking rod PDE6β and cone PDE6α’ subunits. Both rod and cone photoreceptor cells are degenerated with age and all PDE6 subunits degrade in rd10/cpfl1 mice. We expressed cone PDE6α’ in both rods and cones of rd10/cpfl1 mice by adeno-associated virus (AAV)-mediated delivery driven by the ubiquitous, constitutive small chicken β-actin promoter. We show that expression of PDE6α’ rescues rod function in rd10/cpfl1 mice, and the restoration of rod light sensitivity is attained through restoration of endogenous rod PDE6γ and formation of a functional PDE6α’γ complex. However, improved photopic cone responses were achieved only after supplementation of both cone PDE6α’ and PDE6γ’ subunits but not by PDE6α’ treatment alone. We observed a two fold increase of PDE6α’ levels in the eyes injected with both PDE6α’ plus PDE6γ’ relative to eyes receiving PDE6α’ alone. Despite the presence of both PDE6γ’ and PDE6γ, the majority of PDE6α’ formed functional complexes with PDE6γ’, suggesting that PDE6α’ has a higher association affinity for PDE6γ’ than for PDE6γ. These results suggest that the presence of PDE6γ’ augments cone PDE6 assembly and enhances its stability. Our finding has important implication for gene therapy of PDE6α’-associated achromatopsia.
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影响因子：
12.4
作者：
Pang, JJ;Chang, B;Hauswirth, WW
通讯作者：
Hauswirth, WW
影响因子：
4.8
作者：
Guo, Lian-Wang;Muradov, Hakim;Ruoho, Arnold E.
通讯作者：
Ruoho, Arnold E.
影响因子：
4.8
作者：
Mou, HM;Cote, RH
通讯作者：
Cote, RH
影响因子：
4.1
作者：
ARTEMYEV, NO;HAMM, HE
通讯作者：
HAMM, HE
DOI：
10.1073/pnas.91.11.4845
发表时间：
1994-05-24
影响因子：
11.1
作者：
COTE, RH;BOWNDS, MD;ARSHAVSKY, VY
通讯作者：
ARSHAVSKY, VY