Characterization of Regulatory Elements of L11 and L1 Operons in Thermophilic Bacteria and Archaea

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Alisa O. Mikhaylina^1,a*, Ekaterina Y. Nikonova¹, Olga S. Kostareva¹, Wolfgang Piendl^2,b, Matthias Erlacher^3,c, and Svetlana V. Tishchenko¹

¹Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia

²Division of Medical Biochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria

³Division of Genomics and RNomics, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria

^* To whom correspondence should be addressed.

Received October 15, 2020; Revised January 24, 2021; Accepted January 24, 2021

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Ribosomal protein L1 is a conserved two-domain protein that is involved in formation of the L1 stalk of the large ribosomal subunit. When there are no free binding sites available on the ribosomal 23S RNA, the protein binds to the specific site on the mRNA of its own operon (L11 operon in bacteria and L1 operon in archaea) preventing translation. Here we show that the regulatory properties of the r-protein L1 and its domain I are conserved in the thermophilic bacteria Thermus and Thermotoga and in the halophilic archaeon Haloarcula marismortui. At the same time the revealed features of the operon regulation in thermophilic bacteria suggest presence of two regulatory regions.

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KEY WORDS: regulation of expression, L11 operon, L1 operon, r-proteins, mRNA

DOI: 10.1134/S0006297921040027

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