Xiao B, Tu J C, Petralia R S, Yuan J P, Doan A, Breder C D, Ruggiero A, Lanahan A A, Wenthold R J, Worley P F
Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Neuron. 1998 Oct;21(4):707-16. doi: 10.1016/s0896-6273(00)80588-7.
Homer is a neuronal immediate early gene (IEG) that is enriched at excitatory synapses and binds group 1 metabotropic glutamate receptors (mGluRs). Here, we characterize a family of Homer-related proteins derived from three distinct genes. Like Homer IEG (now termed Homer 1a), all new members bind group 1 mGluRs. In contrast to Homer 1a, new members are constitutively expressed and encode a C-terminal coiled-coil (CC) domain that mediates self-multimerization. CC-Homers form natural complexes that cross-link mGluRs and are enriched at the postsynaptic density. Homer 1a does not multimerize and blocks the association of mGluRs with CC-Homer complexes. These observations support a model in which the dynamic expression of Homer 1a competes with constitutively expressed CC-Homers to modify synaptic mGluR properties.
荷马蛋白是一种神经元即时早期基因（IEG），在兴奋性突触中富集，并与1型代谢型谷氨酸受体（mGluRs）结合。在此，我们鉴定了一个源自三个不同基因的荷马相关蛋白家族。与荷马IEG（现称为荷马1a）一样，所有新成员都能结合1型mGluRs。与荷马1a不同的是，新成员组成性表达，并编码一个介导自身多聚化的C端卷曲螺旋（CC）结构域。CC-荷马蛋白形成天然复合物，使mGluRs交联，并在突触后致密区富集。荷马1a不会多聚化，并阻断mGluRs与CC-荷马蛋白复合物的结合。这些观察结果支持了一种模型，即荷马1a的动态表达与组成性表达的CC-荷马蛋白竞争，以改变突触mGluR的特性。
