Table 1.

Quantitative comparison of different fragments of the NG2 proteoglycan. The data shown are taken from Uhgrin et al. (2003) and compare the effects of different regions of NG2 on the inhibition of neurite extension from postnatal cerebellar neurons and on the collapse of the growth cones of newborn rat DRG neurons. Cerebellar neurons were grown on substrates containing either the L1 cell adhesion molecule or a mixture of L1 and NG2 and neurite lengths were measured after 24 h of growth. For growth cone collapse, DRG neurons were plated onto laminin-coated surfaces and soluble proteins added 6 h later. After 20 min, the number of collapsed growth cones was determined. C’ase treated indicates that the protein was treated with chondroitinase ABC prior to testing

Fusion protein	Amino acid residues	EC50 (nm) for growth inhibition	EC50 (nm) for growth cone collapse
ECD	30–6738	3.5	1.8
domain 1-Fc	30–640	4.5	3.1
domain 2-Fc	636–1591	9	3.5
domain 2-Fc		22	>20
C’ase treated
domain 1,2-Fc	30–1591	3	2.5
domain 1,2-Fc		3.5	2.4
C’ase treated
domain 3-Fc	1592–2222	6	2.4