Fig. 3. Gene expression during pronephric development. A) Xpax-8 (pax8) stage 36. Within the pronephros only the pronephric tubules are stained. B) Xlim-1, stage 36. Strongest staining in within the nephrostomes and the pronephric duct, with weaker staining in the pronephric tubules. C). Xwnt-4, stage 35. Strong staining is in the pronephric tubules and weaker staining in the duct. D) Xpax-2, stage 36. E) xWT1, stage 36. F) Double stain with antibodies 3G8 (blue) and 4A6 (red). G) X-ret, stage 28. Staining is strongest in the posterior portion of the pronephric duct.