title: X-epilectin: a novel epidermal fucolectin regulated by BMP signalling.
abstract: This paper reports the cloning and characterisation of a new posterior epidermal marker, X-epilectin, in Xenopus laevis. This gene encodes for a fucolectin, which belongs to the lectin superfamily of carbohydrate binding proteins and specifically binds fucose residues. RT-PCR and in situ hybridisation show that the expression of this gene is switched on during gastrulation and up-regulated during neurula stages and found expressed ubiquitously throughout the epidermis. From tailbud stages, the expression is limited to the dorsal posterior region of the embryo, suggesting that X-epilectin expression is regulated along anteroposterior and dorsoventral gradients during development. In the adult, X-epilectin is mainly expressed in intestinal components, kidney, spinal cord and skin. The effects of growth factors on the regulation of X-epilectin were studied. Change of the fate of animal caps into cement gland or dorsal mesoderm induces a down-regulation of X-epilectin expression in explants treated respectively with ammonium chloride and activin A. We also show that X-epilectin expression is down-regulated by Noggin and tBR and that this effect is inhibited by BMP4 over-expression, suggesting X-epilectin expression is mediated by the BMP signalling pathway.
authors.affiliation: Molecular Physiology, Department of Biological Sciences, Warwick University, Coventry, UK.
authors.forename: Karine
authors.initials: K
authors.lastname: Massé
authors.forename: Rebecca
authors.initials: R
authors.lastname: Baldwin
authors.forename: Mark W
authors.initials: MW
authors.lastname: Barnett
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Jones
mesh_terms: D028341:Activins / Q000378:metabolism; D000595:Amino Acid Sequence; D000643:Ammonium Chloride / Q000494:pharmacology; D000818:Animals; D001483:Base Sequence; D055415:Bone Morphogenetic Protein 4; D052004:Bone Morphogenetic Protein Receptors; D019485:Bone Morphogenetic Proteins / Q000737:chemistry* / Q000378:metabolism*; D002352:Carrier Proteins; D002454:Cell Differentiation; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D015536:Down-Regulation; D005786:Gene Expression Regulation; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D028322:Inhibin-beta Subunits / Q000378:metabolism; D037102:Lectins / Q000096:biosynthesis* / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D011506:Proteins / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D017978:Receptors, Growth Factor / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D012867:Skin / Q000378:metabolism; D013997:Time Factors; D014018:Tissue Distribution; D015854:Up-Regulation; D029867:Xenopus Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000502:physiology*; D014982:Xenopus laevis; D000099176:Noggin Protein
chemical_list: D028341:Activins; D000643:Ammonium Chloride; D055415:Bone Morphogenetic Protein 4; D052004:Bone Morphogenetic Protein Receptors; D019485:Bone Morphogenetic Proteins; D002352:Carrier Proteins; D018076:DNA, Complementary; D028322:Inhibin-beta Subunits; D037102:Lectins; D011506:Proteins; D012313:RNA; D012333:RNA, Messenger; D017978:Receptors, Growth Factor; D029867:Xenopus Proteins; D000099176:Noggin Protein; C502232:X-epilectin, Xenopus; C422405:activin A; C525812:bmp4 protein, Xenopus; C027112:fucose-binding lectin