Contributions of VLDLR and LRP8 in the establishment of retinogeniculate projections

Table 1 Retinogeniculate projection in phenotypes in wild-type and mutant mice

Genotype	Smaller retino-recipient region of vLGN	Sparse retinal projections to IGL	Misrouted retinal axons exiting medial border of LGN	Ectopic retinal projections in dLGN
Control	-	-	-	-
	(0/11)	(0/11)	(0/11)	(0/11)
reln ^rl/rl	++	++	++	-
	7/7	(7/7)	(7/7)	(0/7)
vldlr ^−/−	-	-	-	+/−
	(0/11)	(0/11)	(0/11)	(2/11)
lrp8 ^−/−	-	-	-	-
	(0/9)	(0/9)	(0/9)	(0/9)
vldlr^+/−;lrp8^+/−	-	-	-	-
	(0/9)	(0/9)	(0/9)	(0/9)
vldlr^+/−;lrp8^−/−	-	+	-	+
	(0/6)	(2/6)	(0/6)	(2/6)
vldlr^−/−;lrp8^+/−	+/−	+	+/−	+
	(4/7)	(3/7)	(1/7)	(5/7)
vldlr^−/−;lrp8^−/−	++	++	+/−	++
	(7/7)	(7/7)	(2/7)	(7/7)

The presence of four distinct defects in retinogeniculate projection patterns was assessed in various mutant mice: 1) small retinal projection patterns to vLGN; 2) a region of sparse retinal projections in or adjacent to IGL; 3) retinal axons misrouted out of the medial border of the vLGN and IGL; and 4) an ectopic region of binocular retinal projections in the dorsomedial pole of dLGN. Phenotypes were scored as being: −, absent; +/−, weak and only occasionally present; +, strong but only occasionally present; and ++, strong and highly penetrant. Parentheses indicate the number of mice exhibiting a phenotype compared to the total number of mice analyzed for that genotype. All mice included in these analyses ranged in age from P9 to P23. dLGN, dorsal LGN; IGL, intergeniculate leaflet; LGN, lateral geniculate nucleus; vLGN, ventral LGN.

ISSN: 1749-8104