title: Mechanisms for spatiotemporal regulation of Rho-GTPase signaling at synapses.
abstract: Synapses mediate information flow between neurons and undergo plastic changes in response to experience, which is critical for learning and memory. Conversely, synaptic defects impair information processing and underlie many brain pathologies. Rho-family GTPases control synaptogenesis by transducing signals from extracellular stimuli to the cytoskeleton and nucleus. The Rho-GTPases Rac1 and Cdc42 promote synapse development and the growth of axons and dendrites, while RhoA antagonizes these processes. Despite its importance, many aspects of Rho-GTPase signaling remain relatively unknown. Rho-GTPases are activated by guanine nucleotide exchange factors (GEFs) and inhibited by GTPase-activating proteins (GAPs). Though the number of both GEFs and GAPs greatly exceeds that of Rho-GTPases, loss of even a single GEF or GAP often has profound effects on cognition and behavior. Here, we explore how the actions of specific GEFs and GAPs give rise to the precise spatiotemporal activation patterns of Rho-GTPases in neurons. We consider the effects of coupling GEFs and GAPs targeting the same Rho-GTPase and the modular pathways that connect specific cellular stimuli with a given Rho-GTPase via different GEFs. We discuss how the creation of sharp borders between Rho-GTPase activation zones is achieved by pairing a GEF for one Rho-GTPase with a GAP for another and the extensive crosstalk between different Rho-GTPases. Given the importance of synapses for cognition and the fundamental roles that Rho-GTPases play in regulating them, a detailed understanding of Rho-GTPase signaling is essential to the progress of neuroscience.
authors.affiliation: Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Duman
authors.affiliation: Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
authors.forename: Shalaka
authors.initials: S
authors.lastname: Mulherkar
authors.affiliation: Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Integrative Molecular and Biomedical Sciences Program,Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
authors.forename: Yen-Kuei
authors.initials: YK
authors.lastname: Tu
authors.affiliation: Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
authors.forename: Jinxuan
authors.initials: J
authors.lastname: X Cheng
authors.affiliation: Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Integrative Molecular and Biomedical Sciences Program,Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA. Electronic address: tolias@bcm.edu.
authors.forename: Kimberley F
authors.initials: KF
authors.lastname: Tolias
mesh_terms: D000818:Animals; D001927:Brain Diseases / Q000378:metabolism; D020690:GTPase-Activating Proteins / Q000378:metabolism*; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism; D006801:Humans; D009474:Neurons / Q000378:metabolism; D015398:Signal Transduction; D013569:Synapses / Q000378:metabolism*; D020741:rho GTP-Binding Proteins / Q000378:metabolism*
chemical_list: D020690:GTPase-Activating Proteins; D020662:Guanine Nucleotide Exchange Factors; D020741:rho GTP-Binding Proteins