Characterization of novel human protein methyltransferases

Background: Methyltransferases (MTases) form a large protein family in humans and exert a plethora of functions in the cell. They can methylate several types of biomolecules, including proteins. Protein methylation has been best studied in the case of histone proteins, where the methylation pattern together with other posttranslational modifications constitutes the “histone code” which plays a pivotal role in gene regulation. However, numerous methyl modifications of non-histone proteins have also been reported, but the responsible enzyme has been discovered in only few cases. This, together with the high number of uncharacterized human methyltransferases, suggests that many additional protein MTases that act on non-histone proteins remain to be identified.

Our recent progress and ongoing work: We have identified a novel family of lysine-specific protein methyltransferases (KMTs) (Fig. A) encoded in the human genome (Kernstock et al., 2012). We have so far identified the targets for several of these KMTs, and these targets encompass proteins involved in a wide range of cellular process, including protein folding, protein translation, mitochondrial metabolism and DNA repair (Reviewed in Falnes et al. 2016). For example, we found that the previously uncharacterized human MTase METTL21D (now named VCP-KMT)  methylates Lys-315 in the essential chaperone protein VCP (Fig. B), and this MTase is important for cancer metastasisr cancer metastasis.

Figure: A, Methylation of proteins by lysine (K) methyltransferases (KMTs). B, Trimethylation of VCP on Lys315 by the novel methyltransferase VCP-KMT (Kernstock et al., 2012)

 

Currently, the group focuses on unravelling the function of additional, yet uncharacterized, human MTases, many of which are involved in protein lysine methylation, but we are also studying MTases that target other substrates, e.g. DNA and RNA.  

 

The actual project: In the proposed master project, you will be investigating a novel human MTase. The project will involve a characterization of the enzymatic activity of the MTase on candidate substrates, and the identification (by mutagenesis) of regions/residues in the MTase that are particularly important for function. Moreover, the study will use gene knock-out (CRISPR/Cas9 technology) in human cell culture to address the functional significance of the MTase.

The practical part of the project will be supervised by experienced postdocs/researchers who are focusing their research on various MTases, thus providing an good environment for capable supervision. During this project you will gain work experience in a wide variety of practical techniques, including recombinant DNA technology and mutagenesis, PCR, protein expression and purification, protein biochemistry, enzymatic assays, Western blotting and mammalian cell culture (including gene knock-out cells).

 

Some relevant recent references:

Kernstock,S., Davydova,E., Jakobsson,M., Moen,A., Pettersen,S., Maelandsmo,G.M., Egge-Jacobsen,W. and Falnes§,P.Ø. (2012) Lysine methylation of VCP by a member of a novel human protein methyltransferase family. Nat.Commun., 3, #1038

Falnes§, P.Ø., Jakobsson, M.E., Davydova, E., Ho, A.Y., and Małecki, J. (2016) Protein lysine methylation by seven-β-strand methyltransferases (2016) J. Biochem. J., 473, 1995-2009 (Review article)

Jakobsson, M.E., Moen, A., and Falnes§, P.Ø. (2016) Correspondence: On the enzymology and significance of HSPA1 lysine methylation, Nat.Commun., 7, #11464

Malecki, J., Aileni V.K.,†, Ho, A.Y.Y., Schwarz, J., Moen A., Sørensen, V., Nilges, B.S.,  Jakobsson, M.E., Leidel, S.A.,  Falnes, P.Ø. (2017) The novel lysine specific methyltransferase METTL21B affects mRNA translation through inducible and dynamic methylation of Lys-165 in human eukaryotic elongation factor 1 alpha (eEF1A). Nucl. Acids Res., 45, 4370-4389.

 

Published Apr. 19, 2018 8:13 AM - Last modified July 16, 2018 1:00 PM

Supervisor(s)

Scope (credits)

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