Wnt Sıgnaling Pathway In Embryonic Stem Cells

Öz

One of the major mechanisms for the formation of different cells from the cells with the same genetic information during the development and differentiation, is intracellular signal transmission. One of the most important of these signaling pathways is Wnt. Wnt pathway plays roles in various processes in the embryonic development by the effects on embryonic stem cells. The effects of Wnt pathway on embryonic stem cells seem to be a part of very complex mechanism. The interactions provided by the microenvironment within the cells can generate different answers to the same signal. Pluripotent stem cells have a great importance in regenerative medicine. The most important source of these cells are embryonic stem cells. However, ethical problems hinder the use of these cells. The induced pluripotent stem cells which can be seen as an alternative; have difficulties in the production techniques and carries some problems related to the gene intervention. In this regard quests to reduce or eliminate the need for gene intervention are ongoing. Here in particular, a variety of small molecules that can affect cellular mechanism draws attention. One of the target mechanisms of these molecules is the Wnt signaling pathway. However, a safe and successful method for cellular reprogramming with this pathway has not yet been developed.

Anahtar Kelimeler

• Wnt,Embryonic stem cells,Regenerative medicine

Embriyonik Kök Hücrelerde Wnt Sinyal Yolağı

Öz

Gelişim ve farklılaşmada, aynı genetik bilgiye sahip hücrelerden farklı hücrelerin oluşumunu sağlayan önemli mekanizmalardan biri hücreler arası sinyal iletimidir. Bu yolaklarının başında ise Wnt gelmektedir. Wnt yolağı embriyonik kök hücrelerdeki etkileri ile embriyonik gelişimde çeşitli süreçlerde rol oynamaktadır. Wnt yolağının embriyonik kök hücreler üzerine olan etkileri, oldukça karmaşık bir mekanizmanın parçasıdır. Hücrelerin içinde bulunduğu mikroçevrenin sağladığı etkileşimler aynı sinyale farklı yanıtlar oluşturabilmektedir. Rejeneratif tıp alanında pluripotent kök hücreler büyük önem taşımaktadır. Bu hücrelerin en önemli kaynağı, embriyonik kök hücrelerdir. Ancak etik sorunlar bu hücrelerin kullanımını engellemektedir. Alternatif olarak görülebilecek indüklenmiş pluripotent kök hücreler ise; üretim tekniklerinde zorluklar ve gen müdahalesine bağlı sorunlar taşımaktadır. Bu bakımdan gen müdahalesine gerek duymayacak veya azaltacak arayışlar sürmektedir. Burada özellikle, çeşitli hücresel mekanizmaları etkileyen küçük moleküller dikkat çekmektedir. Bu moleküllerin hedefinde yer alan mekanizmalardan biri de Wnt sinyal yolağıdır. Ancak bu yolak ile geliştirilmiş, hücresel yeniden programlama açısından güvenli ve başarılı bir yöntem henüz bulunmamaktadır. 

Anahtar Kelimeler

• Wnt,Embriyonik kök hücreler,Rejeneratif tıp

Kaynakça

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