- Mice deficient for the HNK-1 sulfotransferase show alterations in synaptic efficacy and spatial learning and memory. Senn, C., Kutsche, M., Saghatelyan, A., Bösl, M.R., Löhler, J., Bartsch, U., Morellini, F., Schachner, M. Mol. Cell. Neurosci. (2002)