First Author | Alessi A | Year | 2006 |
Journal | Exp Cell Res | Volume | 312 |
Issue | 16 | Pages | 3084-95 |
PubMed ID | 16857187 | Mgi Jnum | J:114375 |
Mgi Id | MGI:3688932 | Doi | 10.1016/j.yexcr.2006.06.019 |
Citation | Alessi A, et al. (2006) gamma-Syntrophin scaffolding is spatially and functionally distinct from that of the alpha/beta syntrophins. Exp Cell Res 312(16):3084-95 |
abstractText | The syntrophins are a family of scaffolding proteins with multiple protein interaction domains that link signaling proteins to dystrophin family members. Each of the three most characterized syntrophins (alpha, beta1, beta2) contains a PDZ domain that binds a unique set of signaling proteins including kinases, ion and water channels, and neuronal nitric oxide synthase (nNOS). The PDZ domains of the gamma-syntrophins do not bind nNOS. In vitro pull-down assays show that the gamma-syntrophins can bind dystrophin but have unique preferences for the syntrophin binding sites of dystrophin family members. Despite their ability to bind dystrophin in vitro, neither gamma-syntrophin isoform co-localizes with dystrophin in skeletal muscle. Furthermore, gamma-syntrophins do not co-purify with dystrophin isolated from mouse tissue. These data suggest that the interaction of gamma-syntrophin with dystrophin is transient and potentially subject to regulatory mechanisms. gamma1-Syntrophin is highly expressed in brain and is specifically localized in hippocampal pyramidal neurons, Purkinje neurons in cerebellum, and cortical neurons. gamma2-Syntrophin is expressed in many tissues including skeletal muscle where it is found only in the subsynaptic space beneath the neuromuscular junction. In both neurons and muscle, gamma-syntrophin isoforms localize to the endoplasmic reticulum where they may form a scaffold for signaling and trafficking. |