This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

1jtf

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Revision as of 07:17, 10 July 2019

Crystal Structure Analysis of VP39-F180W mutant and m7GpppG complex

Structural highlights

1jtf is a 1 chain structure with sequence from Vaccinia virus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	,
Related:	1jsz, 1jte
Activity:	Polynucleotide adenylyltransferase, with EC number 2.7.7.19
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[MCE_VACCW] Displays methyltransferase, positive regulation of the poly(A) polymerase and transcription elongation activities. Involved in the modification of both mRNA ends and in intermediate and late gene positive transcription elongation. At the mRNAs 5' end, methylates the ribose 2' OH group of the first transcribed nucleotide, thereby producing a 2'-O-methylpurine cap. At the 3' end, functions as a processivity factor which stimulates the activity of the viral poly(A) polymerase VP55 that creates mRNA's poly(A) tail. In the presence of VP39, VP55 does not dissociate from the RNA allowing tail elongation to around 250 adenylates.^[1] ^[2] ^[3]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The N7-methylguanine portion of the mRNA cap structure interacts with cap-binding proteins via an unusual double-stacking arrangement in which the positively charged cap is sandwiched between two parallel-oriented aromatic protein side chains. Three-dimensional costructures of cap with two mRNA cap-binding proteins, namely, translational initiation factor eIF4E and VP39 (the vaccinia virus-encoded mRNA cap-specific 2'-O-methyltransferase), have heretofore been reported. Despite striking similarities between the two proteins in the double stack with the cap, the stack differs most notably in the species of stacked side chain donated by the protein. Whereas eIF4E employs two tryptophans, VP39 uses a tyrosine and a phenylalanine. Here, we have generated tryptophan substitutions in VP39. Tryptophan substitution was shown, crystallographically, not to disrupt the maintenance of a bona fide parallel stack. However, the single-tryptophan and double-tryptophan substitutions were associated with increased affinity for cap nucleoside by factors of 10 and 50, respectively. VP39 interacted more strongly with a true substrate (containing portions of RNA downstream of the cap in addition to the cap itself) than with isolated cap nucleoside, by several orders of magnitude. VP39 mutants with tryptophan substitution at position 180 exhibited apparent defects in substrate catalytic rate during the first turnover cycle, indicating the possibility of an exquisite sensitivity of the catalytic center to subtle changes in substrate position brought about by alterations in the cap-binding slot. The X-ray structure of VP39 with a genuine nucleobase analogue of N7-methylguanosine, namely, N7,9-dimethylguanine, indicated that the N7-methylguanosine rotational orientation within the stack is a property of the cap nucleobase itself.

The "cap-binding slot" of an mRNA cap-binding protein: quantitative effects of aromatic side chain choice in the double-stacking sandwich with cap.,Hu G, Oguro A, Li C, Gershon PD, Quiocho FA Biochemistry. 2002 Jun 18;41(24):7677-87. PMID:12056899^[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Schnierle BS, Gershon PD, Moss B. Cap-specific mRNA (nucleoside-O2'-)-methyltransferase and poly(A) polymerase stimulatory activities of vaccinia virus are mediated by a single protein. Proc Natl Acad Sci U S A. 1992 Apr 1;89(7):2897-901. PMID:1313572
↑ Gershon PD, Ahn BY, Garfield M, Moss B. Poly(A) polymerase and a dissociable polyadenylation stimulatory factor encoded by vaccinia virus. Cell. 1991 Sep 20;66(6):1269-78. PMID:1670500
↑ Latner DR, Thompson JM, Gershon PD, Storrs C, Condit RC. The positive transcription elongation factor activity of the vaccinia virus J3 protein is independent from its (nucleoside-2'-O-) methyltransferase and poly(A) polymerase stimulatory functions. Virology. 2002 Sep 15;301(1):64-80. PMID:12359447
↑ Hu G, Oguro A, Li C, Gershon PD, Quiocho FA. The "cap-binding slot" of an mRNA cap-binding protein: quantitative effects of aromatic side chain choice in the double-stacking sandwich with cap. Biochemistry. 2002 Jun 18;41(24):7677-87. PMID:12056899

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1jtf"

@@ Line 1: / Line 1: @@
 ==Crystal Structure Analysis of VP39-F180W mutant and m7GpppG complex==
-<StructureSection load='1jtf' size='340' side='right' caption='[[1jtf]], [[Resolution|resolution]] 2.60&Aring;' scene=''>
+<StructureSection load='1jtf' size='340' side='right'caption='[[1jtf]], [[Resolution|resolution]] 2.60&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[1jtf]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Vaccinia_virus Vaccinia virus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JTF OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1JTF FirstGlance]. <br>
@@ Line 15: / Line 15: @@
 Check<jmol>
   <jmolCheckbox>
-    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/jt/1jtf_consurf.spt"</scriptWhenChecked>
+    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/jt/1jtf_consurf.spt"</scriptWhenChecked>
     <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
     <text>to colour the structure by Evolutionary Conservation</text>
@@ Line 37: / Line 37: @@
 __TOC__
 </StructureSection>
+[[Category: Large Structures]]
 [[Category: Polynucleotide adenylyltransferase]]
 [[Category: Vaccinia virus]]

1jtf

From Proteopedia

Revision as of 07:17, 10 July 2019

Crystal Structure Analysis of VP39-F180W mutant and m7GpppG complex

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox