title: HpSulf, a heparan sulfate 6-O-endosulfatase, is involved in the regulation of VEGF signaling during sea urchin development.
abstract: Cell surface heparan sulfate proteoglycans (HSPGs) play significant roles in the regulation of developmental signaling, including vascular endothelial growth factor (VEGF), fibroblast growth factor, Wnt and bone morphogenetic protein signaling, through modification of their sulfation patterns. Recent studies have revealed that one of the functions of heparan sulfate 6-O-endosulfatase (Sulf) is to remove the sulfate from the 6-O position of HSPGs at the cell surface, thereby regulating the binding activities of heparan sulfate (HS) chains to numerous ligands and receptors in animal species. In this study, we focused on the sea urchin Hemicentrotus pulcherrimus homolog of Sulf (HpSulf), and analyzed its expression pattern and functions during development. HpSulf protein was present throughout development and localized at cell surface of all blastomeres. In addition, the HS-specific epitope 10E4 was detected at the cell surface and partially colocalized with HpSulf. Knockdown of HpSulf using morpholino antisense oligonucleotides (MO) caused abnormal morphogenesis, and the development of MO-injected embryos was arrested before the hatched blastula stage, indicating that HpSulf is necessary for the early developmental process of sea urchin embryos. Furthermore, we found that injection of HpSulf mRNA suppressed the abnormal skeleton induced by overexpression of HpVEGF mRNA, whereas injection of an inactive form of HpSulf mRNA, containing mutated cysteines in the sulfatase domain, did not have this effect. Taken together, these results suggest that HpSulf is involved in the regulation of various signal transductions, including VEGF signaling, during sea urchin development.
authors.affiliation: Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Fujita
authors.forename: Eriko
authors.initials: E
authors.lastname: Takechi
authors.forename: Naoaki
authors.initials: N
authors.lastname: Sakamoto
authors.forename: Noriko
authors.initials: N
authors.lastname: Sumiyoshi
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Izumi
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Miyamoto
authors.forename: Shinya
authors.initials: S
authors.lastname: Matsuura
authors.forename: Toko
authors.initials: T
authors.lastname: Tsurugaya
authors.forename: Koji
authors.initials: K
authors.lastname: Akasaka
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamamoto
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D055785:Gene Knockdown Techniques; D008969:Molecular Sequence Data; D011487:Protein Conformation; D012333:RNA, Messenger / Q000235:genetics; D012617:Sea Urchins / Q000196:embryology*; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D015238:Sulfotransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D015238:Sulfotransferases