Table 1.

Description of some tools available for studying N-cadherin function

Tool	Advantages	Potential Uses	Potential Further Development
Purified EC1 protein	A purified form of the first extracellular domain of N-cadherin that specifically blocks N-cadherin mediated cell-cell interaction at relatively low concentration Can be added to the culture medium of primary neuronal cultures, slice cultures or cell lines	Useful for assaying the function of N-cadherin mediated cell adhesion in axonal and dendritic outgrowth/maintenance, synapse formation/stabilization, spinogenesis and synaptic plasticity in vitro Blocks N-cadherin mediated interaction in all treated cells	The EC1 domain of other classical cadherins can be generated using a similar strategy to block the function of that particular cadherin.
EC1-myc construct	A secreted, soluble form of the first extracellular domain of N-cadherin that specifically blocks N-cadherin mediated cell-cell interaction Can be used in vitro or in vivo to study the effect of blocking N-cadherin mediated interaction in single cells expressing EC1-myc.	Useful for studying the function of N-cadherin mediated cell adhesion in axonal and dendritic outgrowth/maintenance, synapse formation/stabilization, spinogenesis and synaptic plasticity in vitro and in vivo Blocks N-cadherin mediated interaction specifically in the cell expressing EC1-myc Can be used to study cell-autonomous effects of N-cadherin mediated cell adhesion, potentially distinguishing pre- versus post-synaptic requirements	Transgenic mice can be generated using this construct to block N-cadherin mediated cell-adhesion in individual cells in vivo The EC1 domain of other classical cadherins can be generated using a similar strategy to block the function of that particular cadherin.
N-cadherin-HA construct	A N-cadherin construct with an extracellular epitope tag and expressed under an activity-independent promoter Labels surface N-cadherin at high resolution in individual transfected cells in vitro or in vivo	Useful for studying the function of N-cadherin in axonal and dendritic outgrowth/maintenance, synapse formation/stabilization, spinogenesis and synaptic plasticity in vitro or in vivo Can be used to assay the effect of various manipulations on the level of surface N-cadherin in vitro or in vivo	Transgenic mice can be generated using this construct to study the function of N-cadherin mediated cell-adhesion or regulation of surface N-cadherin expression in vivo A fluorescent extracellular tag, possibly even pH sensitive, can be generated to study regulation of N-cadherin trafficking
pCS2min vector	An activity-independent overexpression vector Expresses proteins at a relatively high level in neurons	Can be used in combination with any of the above reagents to drive activity-independent expression	Can be used as a vector for overexpressing any other protein of interest