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Fig. 7. Slit1 can rescue the axonal phenotype caused by RCAS-Irx4 infection. Slit1
expression construct was co-electroporated with the RCAS-Irx4 construct. As
the RCAS-Irx4-transfected cells would produce infectious viral particles that
spread inside the retina, the infected area was larger than the
Slit1-transfected area. Note in the area where a large number of
Slit1-transfected cells were present (R in B; arrowheads in A,B),
axonal phenotypes caused by RCAS-Irx4 infection were largely corrected.
However, in the area that did not have Slit1-transfected cells
(marked with NR in B), the axons were unevenly distributed and excessively
fasciculated. (C) In the area where only a small number of Slit1-transfected
cells were present, axonal phenotype was partially corrected. Interestingly,
most of the transfected cells appear to align accurately with the axon bundles
(arrowheads in C). The area shown in A-C was completely infected by RCAS-Irx4,
confirmed by anti-GAG staining (D and data not shown). (E,F) As a control, an
expression construct encoding GFP was co-electroporated with the RCAS-Irx4
construct. Although a large number of GFP-transfected cells were present in
this area (visible over the staining of anti-GAG antibody, arrowheads in F),
GFP could not rescue the axonal phenotype of RCAS-Irx4 infection and the axons
appeared uneven and excessively fasciculated (E). The broken white arrows in
A-C,E indicate the direction of axon projection toward the optic disc. Scale
bar: 100 µm.