Bidirectional ephrin/Eph signaling in synaptic functions

Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720-3200, USA.
Brain Research (Impact Factor: 2.83). 01/2008; 1184(1):72-80. DOI: 10.1016/j.brainres.2006.11.033
Source: PubMed

ABSTRACT Eph receptors, the largest family of receptor tyrosine kinases, and their membrane bound ligands, the ephrins, are involved in multiple developmental and adult processes within and outside of the nervous system. Bi-directional signaling from both the receptor and the ligand is initiated by ephrin-Eph binding upon cell-cell contact, and involves interactions with distinct subsets of downstream signaling molecules related to specific functions. In the CNS, Ephs and ephrins act as attractive/repulsive, migratory and cell adhesive cues during development and participate in synaptic functions in adult animals. In this review, we will focus on recent findings highlighting the functions of ephrin/Eph signaling in dendritic spine morphogenesis, synapse formation and synaptic plasticity.

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Available from: Jason Aoto, May 05, 2015
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    • "The most prominent central effects were observed in the double ephrin - A2A5 – / – mice , presumably because of re - dundancy within the ephrin - A family . For example , EphA2 – EphA8 receptors are capable of binding to all ephrin - A proteins [ Aoto and Chen , 2007 ] . "
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    ABSTRACT: Eph receptors and ephrin ligands are large families of cell surface proteins which have established roles in axonal growth and guidance. These are well characterized in the visual and somatosensory systems but are less well documented in the auditory pathway. We examined the possible functional role of two ephrin genes (ephrin-A2 and ephrin-A5) in the auditory system by measuring auditory brainstem responses (ABR) to tone bursts from 6 to 30 kHz in ephrin-A2(-/-), ephrin-A5(-/-) and ephrin-A2A5(-/-) (knockout) mice. At high frequencies, the ephrin-A2A5(-/-) mice exhibited thresholds that were significantly lower than in wild-type mice by approximately 20 dB, suggesting ephrin-A2 and ephrin-A5 may have frequency-specific effects on the auditory system. There were also alterations in ABR wave peak amplitudes that were specific to each mouse strain which suggested both peripheral and central involvement of EphA-ephrin-A signalling in auditory function. © 2014 S. Karger AG, Basel.
    Audiology and Neurotology 01/2014; 19(2-2):115-126. DOI:10.1159/000357029 · 1.85 Impact Factor
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    • "Subcellularly, it is enriched in axonal terminals and dendritic spines, localizations that endowed it with the ability to regulate both morphological and functional plasticity of neurons (Aoto and Chen, 2007; Klein, 2009; Lai and Ip, 2009; Pasquale, 2008). Unlike EphB signaling, which generally promoted spine formation and maturation (Aoto and Chen, 2007; Hruska and Dalva, 2012; Klein, 2009; Lai and Ip, 2009), activation of EphA4 by EphrinA-type ligands led to the retraction of dendritic spines. A number of molecules, including Cdk5, have been shown to participate in this process (Bourgin et al., 2007; Fu et al., 2007; Murai et al., 2003; Richter et al., 2007; Zhou et al., 2007). "
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    Neuropharmacology 11/2012; 65. DOI:10.1016/j.neuropharm.2012.10.012 · 4.82 Impact Factor
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    • "In addition, our analysis may clarify potentially important directional information about pathway alterations. For example, the EPH receptor family is known to participate in bidirectional signaling (Aoto and Chen, 2007). The high absolute differences in the shift scores for this diverse family in the ovarian cohort may reflect functionally opposing roles of these bidirectional receptors in oncogenesis. "
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