Requirement of a novel gene, Xin, in cardiac morphogenesis
| Autor: | Qin Wang, Thomas M. Schultheiss, Sylvia Evans, Da-Zhi Wang, Jenny Li-Chun Lin, Sonja L. Krob, Haley S. Williams, Jim J.-C. Lin, Rebecca S. Reiter |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Transcriptional Activation
Proline Molecular Sequence Data Morphogenesis Bone Morphogenetic Protein 2 Chick Embryo In situ hybridization Xenopus Proteins Biology Bone morphogenetic protein DNA-binding protein Mice Species Specificity Transforming Growth Factor beta medicine Animals Tissue Distribution MEF2C Amino Acid Sequence Northern blot Cloning Molecular Muscle Skeletal Molecular Biology Transcription factor Homeodomain Proteins Sequence Homology Amino Acid MEF2 Transcription Factors Gene Expression Regulation Developmental Nuclear Proteins Heart Sequence Analysis DNA Oligonucleotides Antisense Molecular biology DNA-Binding Proteins medicine.anatomical_structure Myogenic Regulatory Factors Somites Bone Morphogenetic Proteins Homeobox Protein Nkx-2.5 Intercalated disc Transcription Factors Developmental Biology |
| Zdroj: | Development. 126:1281-1294 |
| ISSN: | 1477-9129 0950-1991 |
| Popis: | A novel gene, Xin, from chick (cXin) and mouse (mXin) embryonic hearts, may be required for cardiac morphogenesis and looping. Both cloned cDNAs have a single open reading frame, encoding proteins with 2,562 and 1,677 amino acids for cXin and mXin, respectively. The derived amino acid sequences share 46% similarity. The overall domain structures of the predicted cXin and mXin proteins, including proline-rich regions, 16 amino acid repeats, DNA-binding domains, SH3-binding motifs and nuclear localization signals, are highly conserved. Northern blot analyses detect a single message of 8.9 and 5.8 kilo base (kb) from both cardiac and skeletal muscle of chick and mouse, respectively. In situ hybridization reveals that the cXin gene is specifically expressed in cardiac progenitor cells of chick embryos as early as stage 8, prior to heart tube formation. cXin continues to be expressed in the myocardium of developing hearts. By stage 15, cXin expression is also detected in the myotomes of developing somites. Immunofluorescence microscopy reveals that the mXin protein is colocalized with N-cadherin and connexin-43 in the intercalated discs of adult mouse hearts. Incubation of stage 6 chick embryos with cXin antisense oligonucleotides results in abnormal cardiac morphogenesis and an alteration of cardiac looping. The myocardium of the affected hearts becomes thickened and tends to form multiple invaginations into the heart cavity. This abnormal cellular process may account in part for the abnormal looping. cXin expression can be induced by bone morphogenetic protein (BMP) in explants of anterior medial mesoendoderm from stage 6 chick embryos, a tissue that is normally non-cardiogenic. This induction occurs following the BMP-mediated induction of two cardiac-restricted transcription factors, Nkx2.5 and MEF2C. Furthermore, either MEF2C or Nkx2.5 can transactivate a luciferase reporter driven by the mXin promoter in mouse fibroblasts. These results suggest that Xin may participate in a BMP-Nkx2.5-MEF2C pathway to control cardiac morphogenesis and looping. |
| Databáze: | OpenAIRE |
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