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Updated: May 9, 2026
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Grafting of Beads into Developing Chicken Embryo Limbs to Identify Signal Transduction Pathways Affecting Gene Expression
Published on: January 17, 2016
Expression, function and regulation of Evi-1 during embryonic avian development.
P Celá1, S Moravcová Balková, A Bryjová
1Institute of Animal Physiology and Genetics, v.v.i., Academy of Sciences of the Czech Republic, Brno, Czech Republic; Faculty of Science, Masaryk University, Brno, Czech Republic.
Gene Expression Patterns : GEP
|July 9, 2013
Summary
Ecotropical viral integration site 1 (Evi-1) is crucial for embryonic development, particularly in limb and facial structures. Its expression is regulated by FGF signaling and impacts chondrogenesis, suggesting a role in defining cartilage element size.
Area of Science:
- Developmental Biology
- Molecular Biology
- Genetics
Background:
- Ecotropical viral integration site 1 (Evi-1) is a transcription factor vital for embryonic vascularization and cell proliferation.
- The chimeric transcription factor AML1-EVI-1 is implicated in leukemia, acting as a differentiation blocker and proliferation stimulator.
Purpose of the Study:
- To clone and analyze the expression of chicken Evi-1 during embryonic development.
- To investigate the role of Evi-1 in chondrogenesis and its regulation by FGF signaling.
Main Methods:
- Expression analysis of chicken Evi-1 in various embryonic tissues at different developmental stages.
- siRNA-mediated knockdown of Evi-1 in limb micromass cultures to assess its effect on chondrogenesis.
- Treatment of wing mesenchyme with FGFR inhibitors (PD161570 and SU5402) to evaluate Evi-1 regulation by FGF signaling.
Main Results:
- Evi-1 exhibited early expression in pharyngeal arches, brain, and intermediate mesoderm, with later concentration in the second pharyngeal arch and limb mesenchyme.
- Evi-1 expression was prominent in the anterior limb margin but absent in the posterior bud and precartilage blastema, later restricted to perichondrium and interdigital areas.
- Knockdown of Evi-1 significantly reduced chondrogenesis in limb cultures, and FGFR inhibition led to Evi-1 downregulation.
Conclusions:
- Evi-1 plays a significant role in chondrogenesis within the developing limb.
- Evi-1 may act as a mediator of FGF effects and contribute to determining the size of limb cartilage elements.
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