Modomics - A Database of RNA Modifications

ID Card:

Full name: trimethylguanosinesynthase 1
Synonym: PRIP-interacting protein with methyltransferase motif (PIMT)
GI: 317373500
Orf: TGS1
COG: COG2263
UniProt: Q96RS0
Structures: | 3EGI | 3GDH |
Alpha Fold Predicted Structure: AF-Q96RS0-F1
Enzyme type: methyltransferase
Position of modification - modification: n:0 - m2,2,7GpppN
snoRNA:0 - m2,2,7GpppN


PDB Structures:


3EGI

Structure Description:

Title: Methyltransferase domain of human trimethylguanosine synthase TGS1 bound to m7GpppA (inactive form)
Classification: TRANSFERASE
Technique: X-Ray Diffraction
Resolution: 2.21
R value free: 0.252
R value observed:
R value work: 0.21

Abstract of the PDB Structure's related Publication:

Methyltransferases play an important role in the post-transcriptional maturation of most ribonucleic acids. The modification of spliceosomal UsnRNAs includes N2-dimethylation of the m(7)G cap catalyzed by trimethylguanosine synthase 1 (TGS1). This 5'-cap hypermethylation occurs during the biogenesis of UsnRNPs as it initiates the m(3)G cap-dependent nuclear import of UsnRNPs. The conserved methyltransferase domain of human TGS1 has been purified, crystallized and the crystal structure of this domain with bound substrate m(7)GpppA was solved by means of multiple-wavelength anomalous dispersion. Crystal structure analysis revealed that m(7)GpppA binds via its adenosine moiety to the structurally conserved adenosylmethionine-binding pocket, while the m(7) guanosine remains unbound. This unexpected binding only occurs in the absence of AdoMet and suggests an incomplete binding pocket for the m(7)G cap which is caused by the N-terminal truncation of the protein. These structural data are consistent with the finding that the crystallized fragment of human TGS1 is catalytically inactive, while a fragment that is 17 amino acids longer exhibits activity.

Download RCSB-PDB Structures:

Pdb Files   3EGI.pdb   3GDH.pdb  
Pdbx/mmCIF Files   3EGI.cif   3GDH.cif  


Protein sequence:

MCCEKWSRVAEMFLFIEEREDCKILCLCSRAFVEDRKLYNLGLKGYYIRDSGNNSGDQATEEEEGGYSCGTAESHDSKGIGLDESELDSEAELMRSMGLPLQFGRITAHKDFEVSMNTRNKVKIKKKKHQKKYLDEIVQESWRKEYEEDDILASDDPSSIEQYENTRTYELQSKKDTETENPPVENTLSPKLEITEKWEKYWNEYGGGLLWQSWQEKHPGQALSSEPWNFPDTKEEWEQHYSQLYWYYLEQFQYWEAQGWTFDASQSCDTDTYTSKTEADDKNDEKCMKVDLVSFPSSPIMVDNDSSGTSDKDHSEILDGISNIKLNSEEVTQSQLDSCTSHDGHQQLSEVSSKRECPASGQSEPRNGGTNEESNSSGNTNTDPPAEDSQKSSGANTSKDRPHASGTDGDESEEDPPEHKPSKLKRSHELDIDENPASDFDDSGSLLGFKYGSGQKYGGIPNFSHRQVRYLEKNVKLKSKYLDMRRQIKMKNKHIFFTKESEKPFFKKSKILSKVEKFLTWVNKPMDEEASQESSSHDNVHDASTSSDSEEQDMSVKKGDDLLETNNPEPEKCQSVSSAGELETENYERDSLLATVPDEQDCVTQEVPDSRQAETEAEVKKKKNKKKNKKVNGLPPEIAAVPELAKYWAQRYRLFSRFDDGIKLDREGWFSVTPEKIAEHIAGRVSQSFKCDVVVDAFCGVGGNTIQFALTGMRVIAIDIDPVKIALARNNAEVYGIADKIEFICGDFLLLASFLKADVVFLSPPWGGPDYATAETFDIRTMMSPDGFEIFRLSKKITNNIVYFLPRNADIDQVASLAGPGGQVEIEQNFLNNKLKTITAYFGDLIRRPASET

Comments:

Catalyzes the two sequential methylation steps for the conversion of the 7-monomethylguanosine (m7G) caps of snRNAs and snoRNAs to a 2,2,7-trimethylguanosine (m(2,2,7)G) cap structure. The enzyme is specific for guanine, and N7 methylation must precede N2 methylation. Some selenoprotein mRNAs were found to contain 2,2,7-trimethylguanosine (m(2,2,7)G) cap structure and Tgs1 was found to be involved in hypermethylation of these caps.





Alpha Fold Predicted Structure:






Clear Selection and Reset Camera

Protein sequence:

M C C E K W S R V A E M F L F I E E R E D C K I L C L C S R A F V E D R K L Y N L G L K G Y Y I R D S G N N S G D Q A T E E E E G G Y S C G T A E S H D S K G I G L D E S E L D S E A E L M R S M G L P L Q F G R I T A H K D F E V S M N T R N K V K I K K K K H Q K K Y L D E I V Q E S W R K E Y E E D D I L A S D D P S S I E Q Y E N T R T Y E L Q S K K D T E T E N P P V E N T L S P K L E I T E K W E K Y W N E Y G G G L L W Q S W Q E K H P G Q A L S S E P W N F P D T K E E W E Q H Y S Q L Y W Y Y L E Q F Q Y W E A Q G W T F D A S Q S C D T D T Y T S K T E A D D K N D E K C M K V D L V S F P S S P I M V D N D S S G T S D K D H S E I L D G I S N I K L N S E E V T Q S Q L D S C T S H D G H Q Q L S E V S S K R E C P A S G Q S E P R N G G T N E E S N S S G N T N T D P P A E D S Q K S S G A N T S K D R P H A S G T D G D E S E E D P P E H K P S K L K R S H E L D I D E N P A S D F D D S G S L L G F K Y G S G Q K Y G G I P N F S H R Q V R Y L E K N V K L K S K Y L D M R R Q I K M K N K H I F F T K E S E K P F F K K S K I L S K V E K F L T W V N K P M D E E A S Q E S S S H D N V H D A S T S S D S E E Q D M S V K K G D D L L E T N N P E P E K C Q S V S S A G E L E T E N Y E R D S L L A T V P D E Q D C V T Q E V P D S R Q A E T E A E V K K K K N K K K N K K V N G L P P E I A A V P E L A K Y W A Q R Y R L F S R F D D G I K L D R E G W F S V T P E K I A E H I A G R V S Q S F K C D V V V D A F C G V G G N T I Q F A L T G M R V I A I D I D P V K I A L A R N N A E V Y G I A D K I E F I C G D F L L L A S F L K A D V V F L S P P W G G P D Y A T A E T F D I R T M M S P D G F E I F R L S K K I T N N I V Y F L P R N A D I D Q V A S L A G P G G Q V E I E Q N F L N N K L K T I T A Y F G D L I R R P A S E T
100200300400500600700800SequenceGHITBSN

Secondary Structure Alphabet

  • G: 3-turn helix (310helix)
  • H: α-helix
  • I: 𝝅-helix (5 - turn helix)
  • T: Hydrogen Bonded Turn
  • B: β-sheet
  • S: Bend
  • C: Coil (residues not present in any of the above conformations)
  • N: Not assigned

Download PDB Structures & DSSP Secondary Structures:

Alpha Fold Pdb Files   AF-Q96RS0-F1.pdb  
Alpha Fold Pdbx/mmCIF Files   AF-Q96RS0-F1.cif  





Publications: