İpek Böceği Bombyx mori’ nin Orta Bağırsağında Açlık Stresinin Etkilerinin Araştırılması

Öz

Organizmalar, evrimleri sırasında değişen beslenme koşullarına uyum sağlamak için depo moleküllerinin mobilizasyonu ve otofajinin aktivasyonu gibi çeşitli mekanizmalar geliştirmiştir. Bu çalışmada, farklı günlerde aç bırakılan ipekböceği Bombyx mori L., 1758 (Lepidoptera: Bombycidae) larvalarının orta bağırsağındaki adaptif tepkilerin mekanizması araştırılmıştır. Çalışma 2018-2020 yılları arasında Ege Üniversitesi böcek fizyolojisi araştırma laboratuvarı ve ipekböceği kültür laboratuvarında yapılmıştır. Bu amaçla hematoksilen&eozin boyama ile orta bağırsağın histolojik yapısı incelenmiş ve protein, şeker, glikojen ve lipid içerikleri belirlenmiştir. Otofaji belirteçleri olarak lizozomal enzim aktiviteleri ölçülmüş ve otofaji ile ilgili genlerin (mTOR, ATG8 ve ATG12) ifadeleri qRT-PCR ile analiz edilmiştir. Sonuçlar, açlık stresinin başlama zamanına bağlı olarak, otofajinin, açlık koşulları altında adaptif bir yanıt olarak hiçbir rolü olmadığını veya larva-pupa metamorfozu sırasında hücre ölümünün bir parçası olarak meydana gelen otofajiden çok daha ılımlı bir seviyede meydana geldiğini göstermiştir.

Anahtar Kelimeler

• Pul kanatlılar
• Sindirim kanalı
• Programlı hücre ölümü
• ATG genleri

Investigation of the Effects of Starvation Stress in the Midgut of the Silkworm Bombyx mori

Öz

During their evolution, organisms have developed various mechanisms to adapt to changing nutritional conditions such as mobilization of storage molecules and activation of autophagy. In this study, the mechanism of adaptive responses in the midgut of the silkworm Bombyx mori L., 1758 (Lepidoptera: Bombycidae) larvae, which were starved for different days, was investigated. The study was carried out at the Insect Physiology Research Laboratory and Silkworm Culture Laboratory at Ege University between 2018 and 2020. For this purpose, the histological structure of the midgut was examined using hematoxylin&eosin staining and its protein, sugar, glycogen, and lipid contents were determined. As autophagy markers, lysosomal enzyme activities were measured and expressions of autophagy-related genes (mTOR, ATG8, and ATG12) were analyzed by qRT-PCR. The results showed that, depending on the time of onset of starvation stress, autophagy plays no role as an adaptive response under starvation conditions or occurs at a much more moderate level than autophagy which happens as part of cell death during larval-pupal metamorphosis.

Anahtar Kelimeler

• Lepidoptera
• digestive canal
• programmed cell death
• ATG genes

Kaynakça

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