Fırat DOĞAN, Ali Rıza BABAOĞLU, Gülizar ACAR KIRMIZI, Seval Bilge DAĞALP

SARS-CoV-2’nin genom organizasyonu

Coronaviridae ailesi Orthocoronavirinae ve Letovirinae olmak üzereiki alt aileden oluşmaktadır. Orthocoronavirinae alt ailesi serolojikve genetik özelliklerine göre alfa, beta, gamma ve delta olmak üzere4 ayrı genusta (cins) incelenmektedir. Coronaviridae ailesinde yeralan viruslar zarflı, 80-220 nm boyutunda ve pleomorfik yapıda olmalarına rağmen, çoğunlukla küresel görünüm sergilemektedir. Buviruslar 20 nm uzunluğunda belirgin ve taç şeklinde trimer spike adıverilen yüzey çıkıntılarına sahiptir. Coronaviruslar büyük RNA genomuna sahip olmaları nedeniyle mutasyon ve rekombinasyon türügenom değişimleri, bu viruslarda daha fazla görülmektedir. Özellikleyarasa CoV'larının doğada çok sayıda farklı konakçı türünde sirküleolabilmesi, rekombinasyon ve mutasyon oranının artmasına ve yenipatojen CoV'ların ortaya çıkmasına yol açabilmektedir. Coronavirusların çoğalması konak hücrenin sitoplazmasında gerçekleşmektedir.Bu viruslar replikasyon için ilk önce S proteini ile hücre yüzey reseptörlerine tutunurlar. CoV'un konakçıda enfeksiyon oluşturabilmesinde ve doku tropizminde temel belirleyici, virus S proteini ve konakhücre yüzey reseptörü arasındaki ilişkidir. SARS-CoV-2, Anjiyotensindönüştürücü enzim 2'nin (Angiotensin-converting enzyme 2 - ACE2)farklı bölgelerine bağlanmaktadır. ACE2, kardiak fonksiyonu ve kanbasıncının dengelenmesi için önemli bir hücre yüzeyi çinko-bağlayıcı karboksipeptidaz olarak tanımlanmaktadır. SARS-CoV-2'nin, yenibir pandeminin etiyolojik ajanı olarak tanımlanması ile birlikte yarasa kökenli Coronavirusların moleküler biyolojisi ve patogenezine yönelik ilgiyi bir kez daha uyandırmıştır. Bu çalışmalar SARS-CoV-2’yekarşı oldukça kısa bir süre içinde spesifik antiviral ajan ve aşılarıngeliştirilmesi için kullanılabilecek çok sayıda fonksiyonel ve yapısalbilgi üretmiştir

Genomic organization of SARS-CoV-2

The Coronaviridae family consists of two subfamilies Orthocoronavirinae and Letovirinae. Orthocoronavirinae subfamily is examined in 4 different genus (genus) as alpha, beta, gamma and delta according to their serological and genetic characteristics. Although the viruses in the Coronaviridae family are enveloped, 80-220 nm in size and pleomorphic, they mostly exhibit a spherical appearance. These viruses have prominent and crown-shaped surface protrusions called trimer spikes, 20 nm long. Since coronaviruses have a large RNA genome, genomic changes such as mutation and recombination are more common in these viruses. n particular, the fact that bat CoVs can circulate in many different host species in nature may lead to an increase in the rate of recombination and mutation and the emergence of new pathogen CoVs. The reproduction of coronaviruses takes place in the cytoplasm of the host cell. These viruses first attach to cell surface receptors with S protein for replication. The main determinant of CoV's ability to infect the host and tissue tropism is the relationship between virus S protein and host cell surface receptor. SARS-CoV-2 binds to different regions of angiotensin converting enzyme-2 (ACE2). ACE2 is defined as an important cell surface zinc-binding carboxypeptidase for cardiac function and balancing of blood pressure. With the identification of SARS-CoV-2 as a etiological agent of a new pandemic, it has once again aroused interest in the molecular biology and pathogenesis of bat-borne coronaviruses. These studies have produced a lot of functional and structural information that can be used for the development of specific antiviral agents and vaccines against SARS-CoV-2 in a very short time.

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