Nematod Caenorhabditis Elegans'ın Oksijen Seviyesine Bağlı Hareket ve Sürü Oluşturma Davranışının Belirlenmesi

Nematod Caenorhabditis elegans (C. elegans) doğada sürü davranışı gösterebilen bir model organizmadır. C. elegans sürü oluşturma özellikleri, bulunduğu ortamdaki oksijen ve bakteri seviyesi ile direk ilişkilidir. Bu etkilerin karmaşık bir sonucu olarak C. elegans kendiliğinden organize olabilen kalabalık gruplar oluşturmaktadır. Bu grupların kolektif hareketleri canlının hız profilinin oksijen seviyesine bağlılığı tarafından kontrol edilmekte ve yoğunluğa göre farklı faz geçişleri göstermektedir. Bu grup oluşturma davranışlarını kontrol eden, gerçek hız profili tam olarak tespit edilememektedir. Bu çalışmada C. elegans’ın hareket hızının, bulunduğu ortamın oksijen seviyesine bağlılığı tespit edilmiştir. Bu çalışmanın ayırıcı özelliği, canlının hem kuyruk hem de kafa sinirleri aynı ortamı algılayacak şekilde, bir sıvı ortam ölçümü ile yapılmasıdır. Oksijen seviyeleri fiber optik oksijen sensörü ile belirlenmiş ve hareket hızı ile bağlantısı tespit edilmiştir. Tespit edilen deneysel hız profili, faz ayrımı prensibi kullanılarak sürü oluşturma davranışı matematiksel olarak modellenmiştir.
Anahtar Kelimeler:

C. elegans, hareket, sürü

Investigation of oxygen-dependent motility and swarming behavior in nematode Nematode Caenorhabditis Elegans

Model organism Caenorhabditis elegans can perform swarming behavior in nature. This behavior is intricately linked to the presence of bacteria and oxygen levels in the environment. The complex interplay of all these factors drives the emergence of a self-organized swarming response. The collective motility of this behavior is particularly controlled by the oxygen-dependent velocity profile of the animals which triggers phase separation into dense and dilute clusters. However, the exact velocity profile leading to this transition has not been determined yet. In this study, we experimentally identified this missing information by using a liquid environment. The main difference in this measurement is to use liquid culture to be able to stimulate both head and tail neurons with the same oxygen level. We utilized fiber optic-based sensors to precisely measure oxygen levels that correlated with the animal’s velocity. Finally, based on these experimental results, we modeled swarming behavior using phase separation principles.

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