New Generation Genome Editing Techniques: ZFNs, TALENs, CRISPRs and Their Usage in Plant Research

Öz

ZFNs, TALENs and CRISPRs are the new generation genome editing tools functioning by binding a specified target region on DNA. Using one of these techniques, target genes could be edited by insertion/deletions. It is also possible to replace nucleotides in target genes via homologous recombination. Compared to the current methods, new generation genome editing is faster, easier, more efficient and less expensive. This review covers how and where new generation genome editing techniques can be used, comparison one to another, and highlights applications in plant genetic engineering and plant breeding. Furthermore, the release of genome edited plants to the environment and current regulations in the world are discussed. It is predicted that improvements in binding and excising efficacy of new generation genome editing techniques would take the current research one step further, and would be a major aid to plant breeding that would lead to generating crop varieties with higher yield, quality and tolerance to biotic and abiotic stresses.

Anahtar Kelimeler

• ZFN
• TALEN
• CRISPR
• gene silencing

Yeni Nesil Genom Düzenleme Teknikleri: ZFN, TALEN, CRISPR’lar ve Bitkilerde Kullanımı

Öz

ZFN, TALEN ve CRISPR’lar DNA’da hedeflenen bölgeye bağlanabilmeleri sayesinde genomda düzenleme yapmaya imkân veren yeni nesil genom düzenleme teknikleridir. Bu tekniklerin kullanımı sayesinde hedef genler mutasyona uğratılarak ya da genomdan kesilerek susturulabilmekte, ayrıca genlerde istenilen nükleotidlerin değiştirilmesi de mümkün olabilmektedir. Yapılan genom düzenlemeleri hâlihazırda kullanılan metotlara kıyasla daha hızlı, daha kolay, etkin ve ucuzdur. Bu makalede yeni nesil genom düzenleme tekniklerinin çalışma prensipleri, kullanıldıkları alanlar, tekniklerin birbirleriyle kıyaslanması ve bu teknikler kullanılarak genetik mühendisliği ve ıslahı alanında şu ana kadar yapılmış çalışmalara yer verilmiştir. Makalenin son bölümünde bu tekniklerle yapılan düzenlemeler sonucunda elde edilen bitkilerin doğaya salınımı ve bu konuda mevcut düzenlemelere de değinilmiştir. Yeni nesil genom düzenleme tekniklerinin bağlanma ve kesim etkinliklerinin artırılması mevcut çalışmaları bir adım daha ileriye taşıyarak, daha verimli, kaliteli ve çevresel faktörlere karşı toleranslı çeşitlerin geliştirilmesine imkân tanıyacaktır.

Anahtar Kelimeler

• ZFN
• TALEN
• CRISPR
• gen susturma

Kaynakça

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