Eukaryotic RRNA Modification by Yeast 5-Methylcytosine-Methyltransferases and Human Proliferation-Associated Antigen P120
Overview
Authors
Affiliations
Modified nucleotide 5-methylcytosine (m5C) is frequently present in various eukaryotic RNAs, including tRNAs, rRNAs and in other non-coding RNAs, as well as in mRNAs. RNA:m5C-methyltranferases (MTases) Nop2 from S. cerevisiae and human proliferation-associated nucleolar antigen p120 are both members of a protein family called Nop2/NSUN/NOL1. Protein p120 is well-known as a tumor marker which is over-expressed in various cancer tissues. Using a combination of RNA bisulfite sequencing and HPLC-MS/MS analysis, we demonstrated here that p120 displays an RNA:m5C- MTase activity, which restores m5C formation at position 2870 in domain V of 25S rRNA in a nop2Δ yeast strain. We also confirm that yeast proteins Nop2p and Rcm1p catalyze the formation of m5C in domains V and IV, respectively. In addition, we do not find any evidence of m5C residues in yeast 18S rRNA. We also performed functional complementation of Nop2-deficient yeasts by human p120 and studied the importance of different sequence and structural domains of Nop2 and p120 for yeast growth and m5C-MTase activity. Chimeric protein formed by Nop2 and p120 fragments revealed the importance of Nop2 N-terminal domain for correct protein localization and its cellular function. We also validated that the presence of Nop2, rather than the m5C modification in rRNA itself, is required for pre-rRNA processing. Our results corroborate that Nop2 belongs to the large family of pre-ribosomal proteins and possesses two related functions in pre-rRNA processing: as an essential factor for cleavages and m5C:RNA:modification. These results support the notion of quality control during ribosome synthesis by such modification enzymes.
Zhang Q, Cao Z, He Y, Liu Z, Guo W Transl Oncol. 2024; 52():102257.
PMID: 39733743 PMC: 11743813. DOI: 10.1016/j.tranon.2024.102257.
Chen J, Bai Y, Huang Y, Cui M, Wang Y, Gu Z Sci Adv. 2024; 10(50):eadr1743.
PMID: 39671501 PMC: 11641110. DOI: 10.1126/sciadv.adr1743.
Wang R, Ding L, Lin Y, Luo W, Xu Z, Li W Int J Biol Sci. 2024; 20(15):6241-6254.
PMID: 39664561 PMC: 11628344. DOI: 10.7150/ijbs.101337.
Wiechert F, Unbehaun A, Sprink T, Seibel H, Burger J, Loerke J Nucleic Acids Res. 2024; 53(1.
PMID: 39658079 PMC: 11724314. DOI: 10.1093/nar/gkae1191.
RNA methylation and breast cancer: insights into m6A, m7G and m5C.
Dai Y, Zhao S, Chen H, Yu W, Fu Z, Cui Y Mol Biol Rep. 2024; 52(1):27.
PMID: 39611867 DOI: 10.1007/s11033-024-10138-y.