Essential role of heparan sulfate 2-O-sulfotransferase in chick limb bud patterning and development.
The interactions of heparan sulfate (HS) with heparin-binding growth factors, such as fibroblast growth factors (FGFs), depend greatly on the chain structures. O-Sulfations at various positions on the chain are major factors determining HS structure; therefore, O-sulfation patterns may play a crucial role in controlling the developmental and morphogenetic processes of various tissues and organs by spatiotemporally regulating the activities of heparin-binding growth factors. In a previous study, we found that HS-2-O-sulfotransferase is strongly expressed throughout the mesoderm of chick limb buds during the early stages of development. Here we show that inhibition of HS-2-O-sulfotransferase in the prospective limb region by small inhibitory RNA resulted in the truncation of limb buds and reduced Fgf-8 expression in the apical ectodermal ridge. The treatment also reduced Fgf-10 expression in the mesenchyme. Moreover 2-O-sulfated HS, normally abundant in the basement membranes and mesoderm under ectoderm in limb buds, was significantly reduced in the treated buds. Phosphorylation levels of ERK and Akt were up-regulated in such truncated buds. Thus, we have shown for the first time that 2-O-sulfation of HS is essential for the FGF signaling required for limb bud development and outgrowth.
Kobayashi
Takashi
T
Institute for Molecular Science of Medicine, Aichi Medical University, Nagakute, Aichi 480-1195, Japan.
Habuchi
Hiroko
H
Tamura
Koji
K
Ide
Hiroyuki
H
Kimata
Koji
K
D000818:Animals; D019521:Body Patterning / Q000502:physiology*; D002642:Chick Embryo; D004475:Ectoderm / Q000166:cytology / Q000201:enzymology; D004789:Enzyme Activation / Q000502:physiology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005346:Fibroblast Growth Factors / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000502:physiology*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000502:physiology*; D006497:Heparan Sulfate / Q000378:metabolism*; D018878:Limb Buds / Q000166:cytology / Q000196:embryology / Q000201:enzymology*; D008648:Mesoderm / Q000166:cytology / Q000201:enzymology; D010766:Phosphorylation; D011485:Protein Binding / Q000502:physiology; D011499:Protein Processing, Post-Translational / Q000187:drug effects / Q000502:physiology*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000494:pharmacology; D015238:Sulfotransferases / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics
D048049:Extracellular Signal-Regulated MAP Kinases; D005346:Fibroblast Growth Factors; D006497:Heparan Sulfate; D051057:Proto-Oncogene Proteins c-akt; D034741:RNA, Small Interfering; D015238:Sulfotransferases; C106358:heparan-sulfate 2-sulfotransferase