Cloning and Characterization of Postsynaptic Density 93, a Nitric Oxide Synthase Interacting Protein
Cloning and Characterization of Postsynaptic Density 93, a Nitric Oxide Synthase Interacting Protein
复制标题
DOI：
10.1523/jneurosci.16-23-07407.1996
复制
发表时间：
1996-12
期刊：
影响因子：
--
通讯作者：
J. Brenman;K. S. Christopherson;S. E. Craven;Aaron W. McGee;D. Bredt
中科院分区：
文献类型：
--
作者：
J. Brenman;K. S. Christopherson;S. E. Craven;Aaron W. McGee;D. Bredt
脑内一氧化氮（NO）的形成受神经元NO合成酶（nNOS）对钙/钙调素依赖性的调控。通过nmda型谷氨酸受体的钙内流与nNOS活性有效偶联，而许多其他细胞内钙途径偶联较差。为了阐明这种耦合的可能机制，我们进行了酵母双杂交筛选，以鉴定与nNOS相互作用的蛋白质。鉴定出两个nNOS相互作用蛋白：突触后密度蛋白PSD-93和PSD-95。本文报道了PSD-93的克隆与鉴定。PSD-93在离散的神经元群体和特定的非神经元细胞中表达，并且由于组织特异性选择性剪接，它表现出复杂的分子多样性。与PSD-95一样，PSD-93与nNOS和NMDA受体2B结合。然而，在PSD-95/SAP-90家族成员中，PSD-93在浦肯野神经元细胞体和树突中的表达是独特的。我们还证明了nNOS的N端PDZ结构域是必需的，但它不足以与PSD-93/95相互作用。鉴于PSD-93和PSD-95都含有nNOS和NMDA受体的多个潜在结合位点，涉及PSD-93/95寡聚物的复合物可能有助于解释nNOS与NMDA受体的功能和物理偶联。
Nitric oxide (NO) formation in brain is regulated by the calcium/calmodulin dependence of neuronal NO synthase (nNOS). Calcium influx through NMDA-type glutamate receptors is efficiently coupled to nNOS activity, whereas many other intracellular calcium pathways are poorly coupled. To elucidate possible mechanisms responsible for this coupling, we performed yeast two-hybrid screening to identify proteins that interact with nNOS. Two nNOS interacting proteins were identified: the postsynaptic density proteins PSD-93 and PSD-95. Here, we report the cloning and characterization of PSD-93. PSD-93 is expressed in discrete neuronal populations as well as in specific non-neuronal cells, and it exhibits complex molecular diversity attributable to tissue-specific alternative splicing. PSD-93, like PSD-95, binds to nNOS and to the NMDA receptor 2B. PSD-93, however, is unique among PSD-95/SAP-90 family members in its expression in Purkinje neuron cell bodies and dendrites. We also demonstrate that the PDZ domain at the N terminus of nNOS is required, but it is not sufficient for interaction with PSD-93/95. Given that PSD-93 and PSD-95 each contain multiple potential binding sites for nNOS and the NMDA receptor, complexes involving oligomers of PSD-93/95 may help account for the functional as well as the physical coupling of nNOS to NMDA receptors.