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5'-End sequencing in Saccharomyces cerevisiae offers new insights into 5'-ends of tRNAH is and snoRNAs.

ABSTRACT: tRNAH is guanylyltransferase (Thg1) specifies eukaryotic tRNAH is identity by catalysing a 3'-5' non-Watson-Crick (WC) addition of guanosine to the 5'-end of tRNAH is . Thg1 family enzymes in Archaea and Bacteria, called Thg1-like proteins (TLPs), catalyse a similar but distinct 3'-5' addition in an exclusively WC-dependent manner. Here, a genetic system in Saccharomyces cerevisiae was employed to further assess the biochemical differences between Thg1 and TLPs. Utilizing a novel 5'-end sequencing pipeline, we find that a Bacillus thuringiensis TLP sustains the growth of a thg1? strain by maintaining a WC-dependent addition of U-1 across from A73 . Additionally, we observe 5'-end heterogeneity in S. cerevisiae small nucleolar RNAs (snoRNAs), an observation that may inform methods of annotation and mechanisms of snoRNA processing.

SUBMITTER: Dodbele S

PROVIDER: S-EPMC6513681 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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5'-End sequencing in Saccharomyces cerevisiae offers new insights into 5'-ends of tRNAHis and snoRNAs.

Dodbele Samantha S Moreland Blythe B Gardner Spencer M SM Bundschuh Ralf R Jackman Jane E JE

FEBS letters 20190404 9

tRNAHis guanylyltransferase (Thg1) specifies eukaryotic tRNAHis identity by catalysing a 3'-5' non-Watson-Crick (WC) addition of guanosine to the 5'-end of tRNAHis . Thg1 family enzymes in Archaea and Bacteria, called Thg1-like proteins (TLPs), catalyse a similar but distinct 3'-5' addition in an exclusively WC-dependent manner. Here, a genetic system in Saccharomyces cerevisiae was employed to further assess the biochemical diffe ...[more]

PMID: 30908619

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