Expression of heparan sulfate (HS) 2-O-sulfotransferase (2-OST) and Glce-A and -B are not always coordinated during early zebrafish development. A-E: Early expression of HS 2-OST in two cell (A), 60% epiboly (B), 2 somite (C), 7 somite (D), and 13 somite (E) stages. F-N: Comparison of HS 2-OST (18 somites, F; 24 hr postfertilization [hpf], G; and 36 hpf, H), C5-epimerase-A (18 somites, I; 24 hpf, J; and 36 hpf, K), and C5-epimerase-B (18 somites, L; 24 hpf, M; and 36 hpf, N). Green arrows indicate areas where expression is stronger or unique to the C5-epimerase genes, black arrows represent areas where expression is similar between 2-OST and epimerase, and red arrows indicate areas where 2-OST is stronger. O: Expression of HS 2-OST at 48 hpf. BA, branchial arches; E, eye; EL, eye lens; FB, forebrain; HB, hindbrain; MB, midbrain; OT, otic vesicle; PF, pectoral fin; S, somites; TB, tail bud.

Heparan sulfate (HS) 2-O-sulfotransferase (2-OST) and C5-epimerase expression in brain and pectoral fin. A-C: Expression of HS 2-OST in a dorsal view of a 24 hr postfertilization (hpf) brain (A), a dorsal view of a 36 hpf brain (B), and a dorsal view of 48 hpf brain and pectoral fin (C). D-F: Expression of GlceA in a dorsal view of a 24 hpf brain (D), a dorsal view of a 36 hpf brain (E), and a dorsal view of a 48 hpf brain and pectoral fin (F). G-I: Expression of GlceB in a dorsal view of a 24 hpf brain (G), a dorsal view of a 36 hpf brain (H), and a dorsal view of 48 hpf brain and pectoral fin (I). The white arrowhead indicates expression in the pectoral fin; black arrowheads indicate lack of pectoral fin expression. E, eye; EL, eye lens; FB, forebrain; HB, hindbrain; MB, midbrain; MHB, midbrain-hindbrain boundary; OT, otic vesicle.