PUBLICATION
Zebrafish IGF genes: gene duplication, conservation and divergence, and novel roles in midline and notochord development
- Authors
- Zou, S., Kamei, H., Modi, Z., and Duan, C.
- ID
- ZDB-PUB-090921-24
- Date
- 2009
- Source
- PLoS One 4(9): e7026 (Journal)
- Registered Authors
- Duan, Cunming
- Keywords
- Zebrafish, Embryos, Notochords, Insulin, Gene expression, Signal peptides, Somites, Vertebrates
- MeSH Terms
-
- Gene Duplication*
- Phylogeny
- Notochord/metabolism*
- Body Patterning
- Signal Transduction
- PubMed
- 19759899 Full text @ PLoS One
Abstract
Insulin-like growth factors (IGFs) are key regulators of development, growth, and longevity. In most vertebrate species including humans, there is one IGF-1 gene and one IGF-2 gene. Here we report the identification and functional characterization of 4 distinct IGF genes (termed as igf-1a, -1b, -2a, and -2b) in zebrafish. These genes encode 4 structurally distinct and functional IGF peptides. IGF-1a and IGF-2a mRNAs were detected in multiple tissues in adult fish. IGF-1b mRNA was detected only in the gonad and IGF-2b mRNA only in the liver. Functional analysis showed that all 4 IGFs caused similar developmental defects but with different potencies. Many of these embryos had fully or partially duplicated notochords, suggesting that an excess of IGF signaling causes defects in the midline formation and an expansion of the notochord. IGF-2a, the most potent IGF, was analyzed in depth. IGF-2a expression caused defects in the midline formation and expansion of the notochord but it did not alter the anterior neural patterning. These results not only provide new insights into the functional conservation and divergence of the multiple igf genes but also reveal a novel role of IGF signaling in midline formation and notochord development in a vertebrate model.
Genes / Markers
Figure Gallery (5 images)
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping