title: Expression and localization of Rdd proteins in Xenopus embryo.
abstract: The previous study has shown that repeated D domain-like (Rdd) proteins, a group of novel secretory proteins consisting of repeated domains of a cysteine-rich sequence, are involved in the process of blood vessel formation in Xenopus embryo. We performed further experiments to examine the localization of Rdd proteins in embryogenesis. Detection of tagged Rdd proteins expressed in blastomeres showed that Rdd proteins formed a high molecular weight complex and existed in the extracellular space. A rabbit antibody against the Rdd synthetic peptide identified a single band of 28 kD in embryonic tissue extract. By whole-mount immunostaining analysis, signal was detected in the regions of inter-somites, vitelline veins, and branchial arches at the tailbud stage. Staining of Rdd was remarkably reduced in the embryos injected with vascular endothelial growth factor Morpholino. We suggest that Rdd proteins interact with a molecule(s) associated with vascular precursor cells.
authors.affiliation: Graduate School of Science and Technology, Niigata University, Niigata, Japan.
authors.forename: Jong-Chan
authors.initials: JC
authors.lastname: Lim
authors.affiliation: Graduate School of Science and Technology, Niigata University, Niigata, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Kurihara
authors.affiliation: Graduate School of Science and Technology, Niigata University, Niigata, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Tamaki
authors.affiliation: Graduate School of Science and Technology, Niigata University, Niigata, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Mashima
authors.affiliation: Graduate School of Science and Technology, Niigata University, Niigata, Japan.
authors.forename: Mitsugu
authors.initials: M
authors.lastname: Maéno
keywords: Antibody; Cysteine-rich; Frog; Vascular cells; Vascular endothelial growth factor