NURCAN UMUR, HAFİZE SEDA VATANSEVER, Ahmet Şükrü UMUR, MAHMUT KEMAL ÖZBİLGİN, Mehmet SELÇUKİ

Analysis of the effects of inhibitor and activator systems (Smad’s proteins) of TGF-βs on chick neural tube closure

TGF-β ve onun hücre içi sinyal iletim yolunu kontrol eden Smad protein ailesinin, erken nörülasyonda rol oynadığı bilinmektedir. Bu çalışmanın amacı, tavuk embriyosunda nöral tüp gelişiminin farklı saatlerinde bir sistem olarak TGF-β1,2,3, Smad 1/2/3, 6 and 7 proteinlerinin dağılımını göstermektir. Bunun için, SPF yumurtaları, 24, 30, 48, 72. saatlerde 37.8±2ºC’de inkübe edildi ve sonrasında embriyolar, immunohistokimyasal ve immünoblotting yöntemleriyle incelendi. Elde edilen sonuçlara göre, tavuk gelişiminin 24, 30 ve 48. saatlerinde (nöral tüp kapanması sırasında) TGF-βs immünreaktivitelerinin (özellikle TGFβ3) var olduğu ve 72. saatte (nöral tüp kapanmasından sonra) azaldığı saptanırken western blotting yöntemi ile TGF-βs sentezinin embriyoların tüm dönemlerinde var olduğu gösterildi. Smad 1/2/3 immunreaktivitesi ve sentezi ise 24. saatte Smad 6 and 7’ ninkinden daha az iken 30. saatte daha yüksekti. Sonuç olarak, TGF-β ailesinin, tavuk nöral tüp gelişiminde rol oynadığı ve salınımının farklı Smad proteinleri tarafından kontrol edildiği düşünülmektedir. Bununla birlikte, immünoblotting sonuçlar, TGF-βs ve Smads proteinlerinin embriyonun tüm doku ve organlarının gelişiminde etkili olduğunu göstermektedir.

Anahtar Kelimeler:

civciv embriyoları, civciv, embriyonik gelişim, tavuk, immunoblatlama, kümes hayvanları, proteinler, sinyal transdüksiyon, dönüştürücü büyüme etkeni

Tavuk nöral tüp kapanmasında TGF-βs inhibitör ve aktivatör sisteminin (Smad’s proteinleri) etkilerinin araştırılması

The families of TGF-βs and Smads proteins that controls its intracellular signaling pathways are known to play a role in early neurulation. The aim of this study is to demonstrate distribution of TGF-βs (1, 2, 3) and Smads (1/2/3, 6, 7) proteins as a system in different hours of neural tube development of chick embryos. The SPF eggs were incubated at 37.8±2ºC for $24^{th}$, $30^{th}$, $48^{th}$ , $72^{nd}$ h. After that, embryos were examined using immunohistochemistry and western blotting techniques. To the results, TGFβs immunoreactivities (particularly TGF-β3) at the $24^{th}$, $30^{th}$ and $48^{th}$ h of chick development (during neural tube closure) were determined and decreased at the $72^{nd}$ h (after neural tube closure), but expressions of TGF-βs were detected in all stage of embryos in western blotting. While Smad 1/2/3 immunoreactivitiy and expression was less than that of the Smad 6 and 7 at the $24^{th}$, it was increased at the $30^{th}$ h. Smads proteins immunoreactivities were decresead at the $72^{nd}$ h. In conclusion, the members of TGF-βs are play a role in chick neural tube closure, the secretions of TGF-βs are controlled different Smad proteins. In addition, immunoblotting results showed that TGF-βs and Smads proteins were effective in the development of all tissues and organs of the embryos.

Keywords:

chick embryos, chicks, embryonic development, fowls, immunoblotting, poultry, proteins, signal transduction, transforming growth factor,

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