XB-ART-40575Proc Natl Acad Sci U S A November 10, 2009; 106 (45): 18890-6.
Long-range retrograde spread of LTP and LTD from optic tectum to retina.
Neural activity can induce persistent strengthening or weakening of synapses, known as long-term potentiation (LTP) or long-term depression (LTD), respectively. As potential cellular mechanisms underlying learning and memory, LTP and LTD are generally regarded as synapse-specific "imprints" of activity, although there is evidence in vitro that LTP/LTD may spread to adjacent synapses. Here, we report that LTP and LTD induced in vivo at retinotectal synapses of Xenopus tadpoles undergo rapid long-range retrograde spread from the optic tectum to the retina, resulting in potentiation and depression of bipolar cell synapses on the dendrites of retinal ganglion cells, respectively. The retrograde spread of LTP and LTD required retrograde signaling initiated by brain-derived neurotrophic factor and nitric oxide in the tectum, respectively. Such bidirectional adjustment of the strength of input synapses in accordance to that of output synapses may serve to coordinate developmental refinement and learning functions of neural circuits.
PubMed ID: 19887635
PMC ID: PMC2776453
Article link: Proc Natl Acad Sci U S A
Species referenced: Xenopus laevis
Genes referenced: ntrk2
Morpholinos: ntrk2 MO2
References [+] :
Alsina, Visualizing synapse formation in arborizing optic axons in vivo: dynamics and modulation by BDNF. 2001, Pubmed, Xenbase