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Detection of Alternative Splicing During Epithelial-Mesenchymal Transition
Published on: October 9, 2014
Conservation of CD44 exon v3 functional elements in mammals
Elena Vela1, Josep M Hilari, María Delclaux
1Department of R+D+1, Laboratorio Dr. Echevanne, Barcelona, Spain. evela@echevame.com
BMC Research Notes
|August 20, 2008
Summary
The CD44v3 gene, crucial for growth factor binding, shows high conservation across mammals. This suggests CD44v3 is an exclusive mammalian trait, maintaining key regulatory and functional elements.
Area of Science:
- Molecular Biology
- Genetics
- Evolutionary Biology
Background:
- The CD44 gene features 10 variable exons (v1-v10) enabling alternative splicing into numerous protein isoforms.
- Exon v3 inclusion in mRNA relies on an intronic splicing enhancer, conferring growth factor binding capabilities to CD44.
Purpose of the Study:
- To investigate the evolutionary conservation of CD44v3 splicing regulatory elements and its glycosaminoglycan (GAG) binding site across mammalian species.
- To determine the functional expression of CD44v3 isoforms in mammalian peripheral blood cells.
Main Methods:
- Comparative sequence analysis of CD44v3 across 95 mammalian species.
- Assessment of splicing regulatory elements (3' splice site, exonic splicing enhancer) and the GAG binding site.
- Analysis of CD44v3 isoform expression in peripheral blood cells from various mammalian taxa.
Main Results:
- High conservation of splicing regulatory elements and the GAG binding site within CD44v3 across 95 mammalian species.
- Functional expression of CD44v3 isoforms observed in peripheral blood cells of diverse mammalian groups.
- The GAG attachment site, including the exonic splicing enhancer's Y motif, exhibits significant sequence conservation.
Conclusions:
- Mammalian CD44v3 sequences retain critical splicing regulatory elements and the GAG binding site in conserved positions and sequences.
- The high conservation and presence in mammals, but absence in birds, fish, and reptiles, suggest CD44v3 is a mammalian-specific gene trait.
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