Jul 24, 2012

Abnormal vasculature interferes with optic fissure closure in lmo2 mutant zebrafish embryos

Developmental Biology
Omri WeissAdi Inbal

Abstract

Ocular coloboma is a potentially blinding congenital eye malformation caused by failure of optic fissure closure during early embryogenesis. The optic fissure is a ventral groove that forms during optic cup morphogenesis, and through which hyaloid artery and vein enter and leave the developing eye, respectively. After hyaloid artery and vein formation, the optic fissure closes around them. The mechanisms underlying optic fissure closure are poorly understood, and whether and how this process is influenced by hyaloid vessel development is unknown. Here we show that a loss-of-function mutation in lmo2, a gene specifically required for hematopoiesis and vascular development, results in failure of optic fissure closure in zebrafish. Analysis of ocular blood vessels in lmo2 mutants reveals that some vessels are severely dilated, including the hyaloid vein. Remarkably, reducing vessel size leads to rescue of optic fissure phenotype. Our results reveal a new mechanism leading to coloboma, whereby malformed blood vessels interfere with eye morphogenesis.

  • References31
  • Citations14

References

  • References31
  • Citations14

Citations

Mentioned in this Paper

Embryo
GATA1 protein, human
Structure of Hyaloid Artery
Dominant-Negative Mutation
Fissure
Eye Morphogenesis
Sectioning Technique
Entire Retina
Angiogenic Process
Entire Vein

Related Feeds

Birth Defects

Birth defects encompass structural and functional alterations that occur during embryonic or fetal development and are present since birth. The cause may be genetic, environmental or unknown and can result in physical and/or mental impairment. Here is the latest research on birth defects.

Anemia

Anemia develops when your blood lacks enough healthy red blood cells. Anemia of inflammation (AI, also called anemia of chronic disease) is a common, typically normocytic, normochromic anemia that is caused by an underlying inflammatory disease. Here is the latest research on anemia.