Hp. Jiang et al., PHOSPHOLIPASE-C BETA-4 IS INVOLVED IN MODULATING THE VISUAL RESPONSE IN MICE, Proceedings of the National Academy of Sciences of the United Statesof America, 93(25), 1996, pp. 14598-14601
Expression of G protein-regulated phospholipase C (PLC) beta 4 in the
retina, lateral geniculate nucleus, and superior colliculus implies th
at PLC beta 4 may play a role in the mammalian visual process, A mouse
line that lacks PLC beta 4 was generated and the physiological signif
icance of PLC beta 4 in murine visual function was investigated, Behav
ioral tests using a shuttle bos demonstrated that the mice lacking PLC
beta 4 were impaired in their visual processing abilities, whereas th
ey showed no deficit in their auditory abilities, In addition, the PLC
beta 4-null mice showed 4-fold reduction in the maximal amplitude of
the rod a- and b-wave components of their electroretinograms relative
to their littermate controls, However, recording from single rod photo
receptors did not reveal an significant differences between the PLC be
ta 4-null and wild-type littermates, nor were there any apparent diffe
rences in retinas examined with light microscopy. While the behavioral
and electroretinographic results indicate that PLC beta 4 plays a sig
nificant role in mammalian visual signal processing, isolated rod reco
rding shows little or no apparent deficit, suggesting that the effect
of PLC beta 4 deficiency an the rod signaling pathway occurs at some s
tage after the initial phototransduction cascade and may require cell-
cell interactions between rods and other retinal cells.