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Cilia-like structures anchor the amphioxus notochord to its sheath
Ivana Bočina1, Nikola Ljubešić, Mirna Saraga-Babić
1Department of Biology, University of Split, Teslina, Croatia. bocina@pmfst.hr
Acta Histochemica
|September 11, 2009
Summary
Cilia-like structures on amphioxus notochordal cells may modulate body stiffness. These structures, containing microtubular doublets, potentially influence fluid flow within the notochord during locomotion.
Area of Science:
- Marine Biology
- Developmental Biology
- Biomechanics
Background:
- Body stiffness is crucial for efficient undulatory locomotion in aquatic animals.
- In amphioxus, myosepta transmit muscle forces to the notochord, highlighting the notochord's role in locomotion.
Purpose of the Study:
- To investigate the ultrastructure of the amphioxus notochord.
- To define the specific supporting role of the notochord in amphioxus locomotion.
Main Methods:
- Transmission electron microscopy (TEM) was used to analyze the ultrastructure of 10 adult amphioxus specimens.
- Immunohistochemistry with dynein and β-tubulin antibodies was employed to characterize specific structures.
Main Results:
- Numerous cilia-like structures were observed on notochordal cells at their attachment sites to the notochordal sheath.
- These structures exhibited a characteristic microtubular arrangement (peripheral and central doublets) and were anchored to the sheath.
- Positive immunohistochemical reactions for dynein and β-tubulin confirmed the presence of these proteins in the cilia-like structures.
Conclusions:
- The identified cilia-like structures may play a role in modulating amphioxus body stiffness.
- Reduced movement of these structures could facilitate internal fluid flow within the notochord, impacting locomotion dynamics.
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