TY - JOUR
T1 - Direct measurement of local raised subplasmalemmal calcium concentrations in growth cones advancing on an N-cadherin substrate
AU - Chadborn, N
AU - Eickholt, B
AU - Doherty, P
AU - Bolsover, S
PY - 2002
Y1 - 2002
N2 - We have used the membrane-localized calcium probe fura-piperazine-C-12 H-25 (FFP-18) to examine cytosolic calcium concentrations in a volume close to the plasmalemma. Although promotion of axon outgrowth by cell adhesion molecules requires extracellular calcium and is correlated with an opening of plasmalemmal channels, conventional indicators cannot detect a change in the calcium concentration in such stimulated growth cones. We have examined calcium signalling in chick retinal ganglion cell growth cones extending along stripes of N-cadherin. Subplasmalemmal calcium concentrations, reported by FFP-18, were significantly higher in these growth cones than in neighbouring growth cones on either fibronectin or polylysine. In contrast, the bulk cytosolic calcium concentration throughout the growth cone, as measured by Fura-2, was identical in growth cones on and off the N-cadherin stripes. Our results suggest that guidance cues can use extremely local calcium signals to control pathfinding decisions.
AB - We have used the membrane-localized calcium probe fura-piperazine-C-12 H-25 (FFP-18) to examine cytosolic calcium concentrations in a volume close to the plasmalemma. Although promotion of axon outgrowth by cell adhesion molecules requires extracellular calcium and is correlated with an opening of plasmalemmal channels, conventional indicators cannot detect a change in the calcium concentration in such stimulated growth cones. We have examined calcium signalling in chick retinal ganglion cell growth cones extending along stripes of N-cadherin. Subplasmalemmal calcium concentrations, reported by FFP-18, were significantly higher in these growth cones than in neighbouring growth cones on either fibronectin or polylysine. In contrast, the bulk cytosolic calcium concentration throughout the growth cone, as measured by Fura-2, was identical in growth cones on and off the N-cadherin stripes. Our results suggest that guidance cues can use extremely local calcium signals to control pathfinding decisions.
UR - http://www.scopus.com/inward/record.url?scp=0036460495&partnerID=8YFLogxK
U2 - 10.1046/j.1460-9568.2002.02033.x
DO - 10.1046/j.1460-9568.2002.02033.x
M3 - Article
SN - 1460-9568
VL - 15
SP - 1891
EP - 1898
JO - European Journal of Neuroscience
JF - European Journal of Neuroscience
IS - 12
ER -