5OSX

Translation initiation factor 4E in complex with m7G(5'S)ppp(5'S)G mRNA 5' cap analog

Summary for 5OSX

• Entry DOI: 10.2210/pdb5osx/pdb
• Descriptor: Eukaryotic translation initiation factor 4E, [(2~{S},3~{S},4~{R},5~{R})-5-(2-azanyl-7-methyl-6-oxidanylidene-3~{H}-purin-7-ium-9-yl)-3,4-bis(oxidanyl)oxolan-2-yl]methylsulfanyl-[[[(3~{R},4~{S})-5-(2-azanyl-6-oxidanylidene-1~{H}-purin-9-yl)-3,4-bis(oxidanyl)oxolan-2-yl]methylsulfanyl-oxidanyl-phosphoryl]oxy-oxidanyl-phosphoryl]oxy-phosphinic acid, POTASSIUM ION, ... (4 entities in total)
• Functional Keywords: protein-ligand complex, translation initiation factor, eif4e, m7g(5's)ppp(5's)g, phosphorothiolate, mrna 5' cap analog, translation
• Biological source: Mus musculus (Mouse)
• Cellular location: Cytoplasm, P-body : P63073
• Total number of polymer chains: 4
• Total formula weight: 90290.69

Authors

Warminski, M.,Nowak, E.,Wojtczak, B.A.,Fac-Dabrowska, K.,Kubacka, D.,Nowicka, A.,Sikorski, P.J.,Kowalska, J.,Jemielity, J.,Nowotny, M. (deposition date: 2017-08-18, release date: 2018-05-02, Last modification date: 2024-01-17)

Primary citation

Wojtczak, B.A.,Sikorski, P.J.,Fac-Dabrowska, K.,Nowicka, A.,Warminski, M.,Kubacka, D.,Nowak, E.,Nowotny, M.,Kowalska, J.,Jemielity, J.
5'-Phosphorothiolate Dinucleotide Cap Analogues: Reagents for Messenger RNA Modification and Potent Small-Molecular Inhibitors of Decapping Enzymes.
J. Am. Chem. Soc., 140:5987-5999, 2018

PubMed Abstract: The 5' cap consists of 7-methylguanosine (mG) linked by a 5'-5'-triphosphate bridge to messenger RNA (mRNA) and acts as the master regulator of mRNA turnover and translation initiation in eukaryotes. Cap analogues that influence mRNA translation and turnover (either as small molecules or as part of an RNA transcript) are valuable tools for studying gene expression, which is often also of therapeutic relevance. Here, we synthesized a series of 15 dinucleotide cap (mGpppG) analogues containing a 5'-phosphorothiolate (5'-PSL) moiety (i.e., an O-to-S substitution within the 5'-phosphoester) and studied their biological properties in the context of three major cap-binding proteins: translation initiation factor 4E (eIF4E) and two decapping enzymes, DcpS and Dcp2. While the 5'-PSL moiety was neutral or slightly stabilizing for cap interactions with eIF4E, it significantly influenced susceptibility to decapping. Replacing the γ-phosphoester with the 5'-PSL moiety (γ-PSL) prevented β-γ-pyrophosphate bond cleavage by DcpS and conferred strong inhibitory properties. Combining the γ-PSL moiety with α-PSL and β-phosphorothioate (PS) moiety afforded first cap-derived hDcpS inhibitor with low nanomolar potency. Susceptibility to Dcp2 and translational properties were studied after incorporation of the new analogues into mRNA transcripts by RNA polymerase. Transcripts containing the γ-PSL moiety were resistant to cleavage by Dcp2. Surprisingly, superior translational properties were observed for mRNAs containing the α-PSL moiety, which were Dcp2-susceptible. The overall protein expression measured in HeLa cells for this mRNA was comparable to mRNA capped with the translation augmenting β-PS analogue reported previously. Overall, our study highlights 5'-PSL as a synthetically accessible cap modification, which, depending on the substitution site, can either reduce susceptibility to decapping or confer superior translational properties on the mRNA. The 5'-PSL-analogues may find application as reagents for the preparation of efficiently expressed mRNA or for investigation of the role of decapping enzymes in mRNA processing or neuromuscular disorders associated with decapping.

PubMed: 29676910
DOI: 10.1021/jacs.8b02597

Experimental method

X-RAY DIFFRACTION (1.92 Å)