Fig. 5. Oligodendrocytes from mice lacking netrin 1 or Dcc exhibit defects in process branching and in myelin-like membrane sheet formation. (A) Representative examples of the morphology of oligodendrocytes derived from wild-type and netrin-1-deficient or Dcc-deficient mice. 40x0.75 n.a. objective. Scale bar: 20 µm. (B) Application of netrin 1 increased branching by oligodendrocytes from Dcc^+/+ and Dcc^+/-, but not from Dcc^-/-, mice. (C) Oligodendrocytes from Dcc^-/- or Ntn1^-/- mice exhibit no difference in branching complexity compared with cells from wild-type and heterozygous littermates. (D) Ntn1^-/- oligodendrocytes exhibit a significant decrease in myelin-like membrane sheet area compared with cells derived from wild-type and heterozygote littermates. (E) Dcc^-/- oligodendrocytes elaborate smaller myelin-like membrane sheets than wild-type and heterozygous littermates. A.U., arbitrary units. ^***P<0.0001 versus control. Error bars indicate s.e.m.