Open Access

Klara R. Mertinkus, J. Tassilo Grün, Nadide Altınçekiç, Jasleen Kaur Bains, Betül Ceylan, Jan Ferner, Lucio Frydman, Boris Fürtig, Martin Hengesbach, Katharina Felicitas Hohmann, Daniel Hymon, Jihyun Kim, Božana Knežić, Mihajlo Novakovic, Andreas Oxenfarth, Stephen Peter, Nusrat Qureshi, Christian Richter, Tali Scherf, Andreas Schlundt, Robbin Schnieders, Harald Schwalbe, Elke Stirnal, Alexey Sudakov, Jennifer Vögele, Anna Wacker, Julia Weigand, Julia Wirmer-Bartoschek, Maria A. Wirtz Martin, Jens Wöhnert

• The ongoing pandemic of the respiratory disease COVID-19 is caused by the SARS-CoV-2 (SCoV2) virus. SCoV2 is a member of the Betacoronavirus genus. The 30 kb positive sense, single stranded RNA genome of SCoV2 features 5′- and 3′-genomic ends that are highly conserved among Betacoronaviruses. These genomic ends contain structured cis-acting RNA elements, which are involved in the regulation of viral replication and translation. Structural information about these potential antiviral drug targets supports the development of novel classes of therapeutics against COVID-19. The highly conserved branched stem-loop 5 (SL5) found within the 5′-untranslated region (5′-UTR) consists of a basal stem and three stem-loops, namely SL5a, SL5b and SL5c. Both, SL5a and SL5b feature a 5′-UUUCGU-3′ hexaloop that is also found among Alphacoronaviruses. Here, we report the extensive 1H, 13C and 15N resonance assignment of the 37 nucleotides (nts) long sequence spanning SL5b and SL5c (SL5b + c), as basis for further in-depth structural studies by solution NMR spectroscopy.