EC Number | Cloned (Comment) | Organism |
---|---|---|
2.1.1.296 | primer extension analysis, functional expression observed of the MT48 gene tagged at the C-terminus with an HA epitope in mt48-/- cells | Trypanosoma brucei |
EC Number | Protein Variants | Comment | Organism |
---|---|---|---|
2.1.1.296 | additional information | silencing of TbMT48 mRNA by RNAi downregulation does not produce a lethal phenotype, as MT48-RNAi trypanosomes remain viable even after 10 days of tetracycline induction, generation of MT48 KO clonal cell lines by homologous recombination with PCR-generated cassettes. An observed defect in cap 4 modification, specific for MT48 ablation, can be complemented by reintroduction of a copy of the MT48 gene into mt48-/- cells | Trypanosoma brucei |
EC Number | Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|---|
2.1.1.296 | 48000 | - |
x * 48000, SDS-PAGE | Trypanosoma brucei |
EC Number | Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
2.1.1.296 | additional information | Trypanosoma brucei | a conventional 5'-terminal structure of eukaryotic mRNAs consists of a 7-methylguanosine (m7G) moiety linked to the first transcribed nucleotide by a 5' to 5' triphosphate bridge resulting in the structure m7GpppN, which is referred to as cap 0, and most often the first and second transcribed nucleotide carry 2'-O-methyl groups (cap 1 and cap 2 structures, respectively). The cap2 methyltransferase, EC 2.1.1.296 transfers the methyl group to the second nucleotide. In contrast, four nucleotides adjacent to the m7G cap are methylated at the SL RNA 5' end to generate a cap 4 structure: m7G-ppp-N6,N6,2'-O-trimethyladenosine-p-2'-O-methyladenosine-p-2'-O-methylcytosine-p-N3,2'-O-methyluridine. The cap 4 structure seems to be restricted to the family Trypanosomatidae | ? | - |
? |
EC Number | Organism | UniProt | Comment | Textmining |
---|---|---|---|---|
2.1.1.296 | Trypanosoma brucei | Q385S9 | - |
- |
EC Number | Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
2.1.1.296 | additional information | a conventional 5'-terminal structure of eukaryotic mRNAs consists of a 7-methylguanosine (m7G) moiety linked to the first transcribed nucleotide by a 5' to 5' triphosphate bridge resulting in the structure m7GpppN, which is referred to as cap 0, and most often the first and second transcribed nucleotide carry 2'-O-methyl groups (cap 1 and cap 2 structures, respectively). The cap2 methyltransferase, EC 2.1.1.296 transfers the methyl group to the second nucleotide. In contrast, four nucleotides adjacent to the m7G cap are methylated at the SL RNA 5' end to generate a cap 4 structure: m7G-ppp-N6,N6,2'-O-trimethyladenosine-p-2'-O-methyladenosine-p-2'-O-methylcytosine-p-N3,2'-O-methyluridine. The cap 4 structure seems to be restricted to the family Trypanosomatidae | Trypanosoma brucei | ? | - |
? | |
2.1.1.296 | additional information | the enzyme builds the cap 4 structure, usage of an assay with digestion with ribonuclease T2, to monitor the presence of 2'-O-modifications at positions +1 to +4 of the SL sequence | Trypanosoma brucei | ? | - |
? | |
2.1.1.296 | S-adenosyl-L-methionine + a 5'-(N7-methyl 5'-triphosphoguanosine)-(2'-O-methyl-purine-ribonucleotide)-(ribonucleotide)-[mRNA] | - |
Trypanosoma brucei | S-adenosyl-L-homocysteine + a 5'-(N7-methyl 5'-triphosphoguanosine)-(2'-O-methyl-purine-ribonucleotide)-(2'-O-methyl-ribonucleotide)-[mRNA] | - |
? |
EC Number | Subunits | Comment | Organism |
---|---|---|---|
2.1.1.296 | ? | x * 48000, SDS-PAGE | Trypanosoma brucei |
EC Number | Synonyms | Comment | Organism |
---|---|---|---|
2.1.1.296 | MT48 | - |
Trypanosoma brucei |
2.1.1.296 | TbMT48 | - |
Trypanosoma brucei |
EC Number | Cofactor | Comment | Organism | Structure |
---|---|---|---|---|
2.1.1.296 | S-adenosyl-L-methionine | binding domain structure, overview | Trypanosoma brucei |
EC Number | General Information | Comment | Organism |
---|---|---|---|
2.1.1.296 | evolution | the enzyme shows significant sequence and structural similarities to vaccinia virus VP39, another cap-specific RNA 2'-O-methyltransferase. TbMT48 or TbMT57 are two protein components of the cap 4 biosynthetic machinery | Trypanosoma brucei |
2.1.1.296 | malfunction | an observed defect in cap 4 modification is a specific effect of MT48 ablation | Trypanosoma brucei |
2.1.1.296 | additional information | enzyme MT48 structural modeling using the VP39 crystal structure as a template, TbMT48 domains involved in S-adenosyl-methionine and cap binding, overview | Trypanosoma brucei |
2.1.1.296 | physiological function | TbMT48 or TbMT57 are two protein components of the cap 4 biosynthetic machinery. The enzymes involved in cap 4 biogenesis, TbMT48 and TbMT57, are encoded by non-essential genes, considering that the SL cap 4 structure is a crucial determinant for trans-splicing competence of the SL RNA | Trypanosoma brucei |