RRC ID 12089
Author diIorio PJ, Runko A, Farrell CA, Roy N.
Title Sid4: A secreted vertebrate immunoglobulin protein with roles in zebrafish embryogenesis.
Journal Dev Biol
Abstract The small members of the immunoglobulin superfamily (IGSF) are a molecularly diverse group of proteins composed solely of immunoglobulin domains. They may be secreted or tethered to the cell mebrane via GPI linkages and are proposed to have important functions in vivo. However, very few small IGSFs have been functionally characterized. During an ongoing in situ hybridization analysis of expressed sequence tags in zebrafish we identified secreted immunoglobulin domain 4 (sid4), a gene encoding a soluble vertebrate protein composed solely of four immunoglobulin domains. Throughout development, sid4 is expressed in regions of the embryo undergoing active cell division and migration. Functional analysis using morpholino antisense oligonucleotides demonstrates that timing of gene expression is normal in morphants, but these embryos are smaller and exhibit defects in epiboly and patterning of axial and prechordal mesoderm. Analyses of chordin, pax2, krox20, and dlx2 expression in morphants demonstrate that early brain patterning is normal but later organization of hindbrain neurons and development of cranial neural crest are perturbed. Levels of apoptosis in morphants were normal prior to 90% epiboly, but were elevated after 10 h post-fertilization (hpf). Apoptosis does not account for early patterning defects of axial mesoderm, but likely contributes to overall reduction in embryo size. Phylogenetic analysis demonstrates that Sid4 is strikingly similar to the fibronectin binding Ig domains of Perlecan/HSPG2. Overall, our data demonstrate a fundamental role for sid4, possibly as a co-factor in extracellular matrix (ECM) interactions, in processes underlying tissue patterning and organogenesis in a vertebrate.
Volume 282(1)
Pages 55-69
Published 2005-6-1
DOI 10.1016/j.ydbio.2005.02.036
PII S0012-1606(05)00130-2
PMID 15936329
MeSH Amino Acid Sequence Animals Apoptosis / genetics Base Sequence Body Patterning / physiology* Cloning, Molecular Cluster Analysis Computational Biology DNA Primers Extracellular Matrix / metabolism* Gene Expression* Immunoglobulins / genetics* Immunoglobulins / metabolism In Situ Hybridization In Situ Nick-End Labeling Microinjections Molecular Sequence Data Neural Crest / metabolism Neurons / metabolism Phylogeny* Rhombencephalon / metabolism Sequence Analysis, DNA Zebrafish / embryology* Zebrafish / metabolism Zebrafish Proteins / genetics* Zebrafish Proteins / metabolism
IF 2.896
Times Cited 3
Zebrafish rw0 (Tg(CM-isl1:GFP))?