The function of SPON1 (spondin 1, Ensembl gene identifier ENSG00000262655) is as follows. Cell adhesion protein that promotes the attachment of spinal cord and sensory neuron cells and the outgrowth of neurites in vitro. May contribute to the growth and guidance of axons in both the spinal cord and the PNS (By similarity). Major factor for vascular smooth muscle cell. .