Fig. 8
Gpc4, Mmp14a and Mmp14b interact to regulate endodermal migration. (A) Relative mRNA levels of mmp14a and mmp14b when compared with eef1a in embryos indicated, as determined by qRT-PCR. ****P<0.0001, Student's t-test. (B) Western blot showing the expression levels of Fn and heat-shock protein 9 (Hspa9, internal control) in control and mmp14a/b RNA-injected embryos. (C-F) Epifluorescence still images of the anterior region of the endodermal sheet in 6s embryos derived from crossing gpc4/Tg(sox17:EGFP) heterozygous fish injected with or without mmp14b RNA. White lines of equivalent length indicate the width of the anterior endodermal sheet. A, anterior; P, posterior. (G) Average width of anterior endoderm. The numbers of embryos analyzed is indicated. ****P<0.0001, #P>0.05; Student's t-test. (H) Proposed model for how Gpc4 regulates the migration of endodermal cells at early segmentation. Magenta arrows indicate decreases in expression; green arrow indicates increase in expression.