Distinct roles of the beta 1-class integrins at the developing and the mature hippocampal excitatory synapse.
Integrins are a large family of cell adhesion receptors involved in a variety of cellular functions. To study their roles at central synapses, we used two cre recombinase lines to delete the Itgb1 beta1 integrin gene in forebrain excitatory neurons at different developmental stages. Removal of the beta1 integrins at an embryonic stage resulted in severe cortical lamination defects without affecting the cellular organization of pyramidal neurons in the CA3 and CA1 regions of the hippocampus. Whereas the hippocampal neurons underwent normal dendritic and synaptic differentiation, the adult synapses exhibited deficits in responses to high-frequency stimulation (HFS), as well as in long-term potentiation (LTP). Deletion of beta1 integrin at a later postnatal stage also impaired LTP but not synaptic responses to HFS. Thus, the beta1-class integrins appear to play distinct roles at different stages of synaptic development, critical for the proper maturation of readily releasable pool of vesicles during early development but essential for LTP throughout adult life.
Huang
Zhen
Z
Department of Physiology, University of California, San Francisco, San Francisco, California 94143, USA.
Shimazu
Kazuhiro
K
Woo
Newton H
NH
Zang
Keling
K
Müller
Ulrich
U
Lu
Bai
B
Reichardt
Louis F
LF
D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D006624:Hippocampus / Q000196:embryology / Q000254:growth & development*; D066298:In Vitro Techniques; D019012:Integrin beta1 / Q000096:biosynthesis / Q000502:physiology*; D017774:Long-Term Potentiation / Q000502:physiology*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009473:Neuronal Plasticity / Q000502:physiology; D013569:Synapses / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology*; D013572:Synaptic Vesicles / Q000502:physiology
D019012:Integrin beta1