The tRNA methyltransferase Dnmt2 is required for accurate polypeptide synthesis during haematopoiesis.
The Dnmt2 enzyme utilizes the catalytic mechanism of eukaryotic DNA methyltransferases to methylate several tRNAs at cytosine 38. Dnmt2 mutant mice, flies, and plants were reported to be viable and fertile, and the biological function of Dnmt2 has remained elusive. Here, we show that endochondral ossification is delayed in newborn Dnmt2-deficient mice, which is accompanied by a reduction of the haematopoietic stem and progenitor cell population and a cell-autonomous defect in their differentiation. RNA bisulfite sequencing revealed that Dnmt2 methylates C38 of tRNA Asp(GTC), Gly(GCC), and Val(AAC), thus preventing tRNA fragmentation. Proteomic analyses from primary bone marrow cells uncovered systematic differences in protein expression that are due to specific codon mistranslation by tRNAs lacking Dnmt2-dependent methylation. Our observations demonstrate that Dnmt2 plays an important role in haematopoiesis and define a novel function of C38 tRNA methylation in the discrimination of near-cognate codons, thereby ensuring accurate polypeptide synthesis.
Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany.
Francesca
F
Tuorto
Department of Translational Oncology, National Center for Tumor Diseases (NCT) and German Cancer Research Center (DKFZ), Heidelberg, Germany.
Friederike
F
Herbst
Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany.
Nader
N
Alerasool
Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany.
Sebastian
S
Bender
Mass Spectrometry Core Unit, MDC, Berlin, Germany.
Oliver
O
Popp
Department of Cellular and Molecular Pathology, German Cancer Research Center, Heidelberg, Germany.
Giuseppina
G
Federico
Helmholtz Junior Research Group Posttranscriptional Control of Gene Expression, German Cancer Research Center (DKFZ) and Center for Molecular Biology of the University of Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany.
Sonja
S
Reitter
Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany.
Reinhard
R
Liebers
Helmholtz Junior Research Group Posttranscriptional Control of Gene Expression, German Cancer Research Center (DKFZ) and Center for Molecular Biology of the University of Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany.
Georg
G
Stoecklin
Department of Cellular and Molecular Pathology, German Cancer Research Center, Heidelberg, Germany.
Hermann-Josef
HJ
Gröne
Mass Spectrometry Core Unit, MDC, Berlin, Germany.
Gunnar
G
Dittmar
Department of Translational Oncology, National Center for Tumor Diseases (NCT) and German Cancer Research Center (DKFZ), Heidelberg, Germany.
Hanno
H
Glimm
Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany f.lyko@dkfz.de.
Frank
F
Lyko
D000818:Animals; D000831:Animals, Newborn; D002454:Cell Differentiation / Q000502:physiology*; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics / Q000378:metabolism*; D006410:Hematopoiesis / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000201:enzymology*; D008745:Methylation; D051379:Mice; D018345:Mice, Knockout; D010012:Osteogenesis / Q000502:physiology; D014176:Protein Biosynthesis / Q000502:physiology*; D012343:RNA, Transfer / Q000235:genetics / Q000378:metabolism
D012343:RNA, Transfer; C491786:Dnmt2 protein, mouse; D004248:DNA (Cytosine-5-)-Methyltransferases
(cytosine‐5) tRNA methylation; Dnmt2; MSCs; haematopoiesis; translation fidelity