THE DILUTE-LETHAL (D(L)) GENE ATTACKS A CA2-CELLS IN MICE( STORE IN THE DENDRITIC SPINE OF PURKINJE)

The absence of smooth endoplasmic reticulum (SER) in the dendritic spi ne of Purkinje cells was found in dilute-lethal (d(l)) mouse cerebella as detected by immunohistochemistry using anti-inositol 1,4,5-triphos phate receptor antibody and electron microscopy. Since SER in the spin e has been suggested to play a crucial role for synaptic regulation as an intracellular Ca2+ store (for reviews, see [Miller, R.J., Frog. Ne urobiol., 37 (1991) 255-285; Simpson, P.B., Challiss, R.A.J. and Nahor ski, S.R., Trends Neurosci., 18 (1995) 299-306]), a neurological defec t, characterized by clonic convulsions with opisthotonus and ataxia, i n the dilute-lethal mouse with homozygous trait may be attributable to the absence of SER in the dendritic spine of Purkinje cells.