Related Experiment Video
Updated: May 20, 2026
09:43
Methods to Test Endocrine Disruption in Drosophila melanogaster
Published on: July 3, 2019
Structural changes under low evolutionary constraint may decrease the affinity of dibenzoylhydrazine insecticides for
M J Zotti1, O Christiaens, P Rougé
1Department of Crop Protection, Ghent University, Ghent, Belgium. mzotti.faem@ufpel.tche.br
Insect Molecular Biology
|July 20, 2012
Summary
Researchers studied the ecdysone receptor (EcR) in insects. A unique cavity in Lepidoptera EcRs may facilitate binding of non-steroidal compounds like tebufenozide, suggesting a novel function.
Area of Science:
- Molecular Evolution
- Structural Biology
- Insect Endocrinology
Background:
- The ecdysone receptor (EcR) is crucial for moulting and metamorphosis in arthropods.
- Understanding genotype-phenotype relationships is key in molecular evolution.
Purpose of the Study:
- Investigate evolutionary constraints on the insect EcR.
- Identify structural features influencing ligand binding and functional divergence.
Main Methods:
- In silico homology modeling of lepidopteran EcR.
- Comparative analysis of evolutionary constraints across insect orders.
Main Results:
- A unique, evolutionarily constrained cavity was identified in Lepidoptera EcR.
- This cavity, absent in older insect groups, may enhance binding of non-steroidal ligands like tebufenozide.
- The Try123 region, exclusive to Lepidoptera EcRs, shows high constraint and may differentiate ligand types.
Conclusions:
- Lepidopteran EcR exhibits unique structural adaptations potentially linked to novel functions.
- The identified cavity and Try123 region represent significant evolutionary innovations in Lepidoptera.
- These findings offer insights into the evolution of ligand specificity in nuclear receptors.
Related Concept Videos
01:28Stability of Conjugated Dienes
Introduction
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
01:29Diels–Alder Reaction: Characteristics of Dienes
The Diels–Alder reaction brings together a diene and a dienophile to form a six-membered ring. Both components have unique characteristics that influence the rate of the reaction.
Characteristics of the diene
Conformation
The simplest example of a diene is 1,3-butadiene, an acyclic conjugated π system. At room temperature, the molecule exists as a mixture of s-cis and s-trans conformers by virtue of rotation around the carbon–carbon single bond. Although the s-trans isomer is more stable, the...
Characteristics of the diene
Conformation
The simplest example of a diene is 1,3-butadiene, an acyclic conjugated π system. At room temperature, the molecule exists as a mixture of s-cis and s-trans conformers by virtue of rotation around the carbon–carbon single bond. Although the s-trans isomer is more stable, the...
01:24Diels–Alder Reaction: Characteristics of Dienophiles
In a Diels–Alder reaction, the diene is usually an electron-rich system and acts as a nucleophile, whereas the dienophile is electron-deficient and functions as an electrophile. Much like the diene, the nature of the dienophile significantly impacts the outcome of the reaction.
Characteristics of Dienophiles
Generally, the best dienophiles are alkenes containing electron-withdrawing substituents such as carbonyl, nitrile, and nitro groups. The feasibility of a Diels–Alder reaction depends on...
Characteristics of Dienophiles
Generally, the best dienophiles are alkenes containing electron-withdrawing substituents such as carbonyl, nitrile, and nitro groups. The feasibility of a Diels–Alder reaction depends on...
01:29Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.
02:30Stability of Substituted Cyclohexanes
This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
01:28Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.