Title Transcript-specific selective translation by specialized ribosomes bearing genome-encoded heterogeneous rRNAs in V. vulnificus CMCP6
Author Younkyung Choi1, Minju Joo1, Wooseok Song1, Minho Lee2, Hana Hyeon1, Hyun-Lee Kim1, Ji-Hyun Yeom1, Kangseok Lee1*, and Eunkyoung Shin1*
Address 1Department of Life Science, Chung-Ang University, Seoul 06974, Republic of Korea, 2Department of Microbiology, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
Bibliography Journal of Microbiology, 60(12),1162-1167, 2022,
DOI 10.1007/s12275-022-2437-9
Key Words ribosome, heterogenous rRNAs, specialized ribosomes, V. vulnificus CMCP6, pathogenic bacteria
Abstract Ribosomes composed of genome-encoded heterogeneous rRNAs are implicated in the rapid adaptation of bacterial cells to environmental changes. A previous study showed that ribosomes bearing the most heterogeneous rRNAs expressed from the rrnI operon (I-ribosomes) are implicated in the preferential translation of a subset of mRNAs, including hspA and tpiA, in Vibrio vulnificus CMCP6. In this study, we show that HspA nascent peptides were predominantly bound to I-ribosomes. Specifically, I-ribosomes were enriched more than two-fold in ribosomes that were pulled down by immunoprecipitation of HspA peptides compared with the proportion of I-ribosomes in crude ribosomes and ribosomes pulled down by immunoprecipitation of RNA polymerase subunit ß peptides in the wild-type (WT) and rrnI-completed strains. Other methods that utilized the incorporation of an affinity tag in 23S rRNA or chimeric rRNA tethering 16S and 23S rRNAs, which generated specialized functional ribosomes in Escherichia coli, did not result in functional I-ribosomes in V. vulnificus CMCP6. This study provides direct evidence of the preferential translation of hspA mRNA by I-ribosomes.