Neuronal pentraxin receptor-1 (NPR1) of 432 aas and 1 or 2 N-terminal TMSs.  May be involved in mediating uptake of synaptic material during synapse remodeling or in mediating the synaptic clustering of AMPA glutamate receptors at a subset of excitatory synapses. NPR is a potent inducer of both excitatory and inhibitory heterologous synapses; knockdown of NPR in cultured neurons decreases the density of both excitatory and inhibitory synapses (Lee et al. 2017). NPR1 is an auxiliary subunit of AMPA receptors (Matthews et al. 2021).