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E. E. Just's broad, yet hidden, influence on modern cell and developmental biology
1Department of Biochemistry and Molecular Biology, Howard University College of Medicine, Washington, DC.
Molecular Reproduction and Development
|September 24, 2019
Summary
E. E. Just's concept of independent irritability, discovered in 1919, influenced Johannes Holtfreter and later Gerhart and Kirschner's theory of facilitated variation, impacting modern cell biology.
Area of Science:
- Cell and Developmental Biology
- Reproductive Biology
Background:
- The centennial of E. E. Just's discovery of the fast block to polyspermy in 2019 highlights his foundational contributions.
- Just's concept of independent irritability describes a cell's ability to respond to diverse signals.
Observation:
- Just observed subtle changes at the egg's surface during fertilization and parthenogenesis.
- These observations led to the postulate of "independent irritability" as a fundamental cell property.
Findings:
- This paper argues that Just's independent irritability influenced Johannes Holtfreter's work on embryonic induction and competence.
- Holtfreter, in turn, influenced Gerhart and Kirschner's theory of facilitated variation, particularly the concept of "weak linkage".
Implications:
- The concept of weak linkage describes the modularity of biological systems, allowing novel trait generation.
- Just's foundational ideas have subtly permeated modern cell and developmental biology through his intellectual successors.
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