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Crystal Structure of the N-terminal Domain of Ryanodine Receptor from Plutella xylostella
Published on: November 30, 2018
Crustacean molt-inhibiting hormone: structure, function, and cellular mode of action
Teruaki Nakatsuji1, Chi-Ying Lee, R Douglas Watson
1Department of Biology, University of Alabama at Birmingham, AL 35294, USA.
Summary
Molt-inhibiting hormone (MIH) regulates crustacean molting by controlling ecdysteroid hormone secretion. Research reveals MIH
Area of Science:
- Crustacean Endocrinology
- Neurohormonal Regulation
- Molting Physiology
Background:
- Molt-inhibiting hormone (MIH) is a key neurohormone regulating ecdysteroid secretion from crustacean Y-organs.
- Understanding MIH's structure, levels, action, and target organ responsiveness is crucial for deciphering molting control.
Purpose of the Study:
- To review current knowledge on molt-inhibiting hormone (MIH) in Crustacea.
- To highlight recent findings on MIH structure, gene, titers, cellular mechanisms, and Y-organ responsiveness.
Main Methods:
- Analysis of protein sequences and cDNA for MIH structure.
- Measurement of MIH levels in eyestalks and hemolymph.
- Investigation of cellular signaling pathways (cGMP, cAMP) and receptor binding in Y-organs.
Main Results:
- Multiple MIH/MIH-like forms identified, suggesting molecular polymorphism.
- Hemolymphatic MIH titers show species-specific variations.
- cGMP is favored as the second messenger in MIH action; Y-organ responsiveness is modulated by phosphodiesterase activity.
Conclusions:
- MIH regulation of ecdysteroidogenesis involves complex signaling pathways and stage-specific Y-organ responsiveness.
- Calcium may influence ecdysteroidogenesis via calcium/calmodulin-dependent phosphodiesterase (PDE1).
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