Xeno-Nükleik Asitler ve XNA Dünyası

İnsan gereksinimlerini karşılamak için günümüzde yeni organizmalar ve biyolojik sistemler oluşturulmaktadır. Sentetik biyoloji, doğada var olmayan organizmaları, biyolojik bileşenleri ve işlevleri oluşturmak için ya da varolan biyolojik sistemlere yeni işlev yaptırabilmek için yeniden tasarlar ve modeller oluşturur. Sentetik biyoloji, biyolojinin mühendisliğidir, in vitro genetik olarak da tanımlanır. Sentetik genomik ise kimyasal sentezle tam bir genomu ya da genomun bir kısmını oluşturabilecek teknolojik çalışmaları kapsar. Santral dogma olarak bilinen evrensel genetik bilgi akışında hücrelerimiz doğal nükleik asit olan DNA'yı okuyarak işlevsel RNA ve protein oluşturur. Xeno nükleik asitler (XNA'lar) ilk kez Herdewijn ve Marlier tarafından kimyasal yolla ortaya çıkarılmış yeni bir türev nükleik asit sınıfıdır. XNA'lar, doğal olmayan nükleik asit omurgalı sentetik genetik polimerlerdir. Doğal genomlarda nükleik asiti oluşturan, replike olan ve sayısı dört olan (GACT) yapıtaşlarına, 1990'da kimyacıların başlattığı genişletilmiş yapay genetik bilgi sistemlerinde yeni yapıtaşları eklenmiştir. Baz çifti sayısı da üçten daha fazlasına çıkarılmıştır. Önceki genetik bilgilerin depolandığı GACT'den oluşan DNA kütüphaneleri, en azından DNA'da Z:P baz çifti şeklinde eşleşebilen GACTZP nükleotidleriyle zenginleştirilmiştir. Genetik kodun düzenlenmesi (genom editing) ve histon kodunun düzenlenmesi (epigenom editing) ile yeniden tasarlanan araştırmalarda şaşırtan sonuçlar vermiş ve pek çok sorunun çözümüne yönelik yeni ufuklar açmıştır. kromatinler, tıpta, biyoteknolojik ve temel biyolojik.

Xeno-Nucleic Acids and the World of XNA

Today, new organisms and biological systems have been formed to meet human existent organisms in nature to make biological components and biological systems or to perform new functions in existing organisms. Synthetic biology which is an engineering of biology is also defined as in vitro genetics. Synthetic genomics covers the technological studies containing chemical synthesis of a portion of the genome or complete genome. In central dogma known as universal flow of genetic information, our cells use DNA, a natural nucleic acid, to make functional RNA and protein constructs. Xeno-nucleic acids (XNAs) are new nucleic acid derivatives and discovered chemically by Herdewijn and Marlier. XNAs are synthetic genetic polymers with unnatural nucleic acid backbone. New building blocks have been added to the four main building blocks (GATC) which constitutes natural genomes and replicates, in the extended artificial genetic information systems in 1990, started by chemists. The number of base pairs have been increased more than three. DNA libraries consisting of GACTs that store earlier genetic data have been enriched with GACTZP nucleotides which can at least pair within the DNA in form of Z:P. Redesigned chromatins by arranging of the genetic code (genome editing) and arranging of the histone code (epigenome editing) have produced surprising results and opened new horizons for the solution of many problems in medicine, biotechnology and basic biological researchs.

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