CoChat
Sign Up
Cited by 175Glycosylation and Glycoproteins ResearchCarbohydrate Chemistry and SynthesisEnzyme Structure and Function

Dynamic Association between the Catalytic and Lectin Domains of Human UDP-GalNAc:Polypeptide α-N-Acetylgalactosaminyltransferase-2

Open access
Fritz, Timothy A., Raman, Jayalakshmi, Tabak, Lawrence A.·2006·Journal of Biological Chemistry
DOI 10.1074/jbc.m513590200
Open this paper in CoChat — free accountOpen PDF

Abstract

The family of UDP-GalNAc:polypeptide alpha-N-acetylgalactosaminyltransferases (ppGalNAcTs) is unique among glycosyltransferases, containing both catalytic and lectin domains that we have previously shown to be closely associated. Here we describe the x-ray crystal structures of human ppGalNAcT-2 (hT2) bound to the product UDP at 2.75 A resolution and to UDP and an acceptor peptide substrate EA2 (PTTDSTTPAPTTK) at 1.64 A resolution. The conformations of both UDP and residues Arg362-Ser372 vary greatly between the two structures. In the hT2-UDP-EA2 complex, residues Arg362-Ser373 comprise a loop that forms a lid over UDP, sealing it in the active site, whereas in the hT2-UDP complex this loop is folded back, exposing UDP to bulk solvent. EA2 binds in a shallow groove with threonine 7 positioned consistent with in vitro data showing it to be the preferred site of glycosylation. The relative orientations of the hT2 catalytic and lectin domains differ dramatically from that of murine ppGalNAcT-1 and also vary considerably between the two hT2 complexes. Indeed, in the hT2-UDP-EA2 complex essentially no contact is made between the catalytic and lectin domains except for the peptide bridge between them. Thus, the hT2 structures reveal an unexpected flexibility between the catalytic and lectin domains and suggest a new mechanism used by hT2 to capture glycosylated substrates. Kinetic analysis of hT2 lacking the lectin domain confirmed the importance of this domain in acting on glycopeptide but not peptide substrates. The structure of the hT2-UDP-EA2 complex also resolves long standing questions regarding ppGalNAcT acceptor substrate specificity.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1074/jbc.m513590200

Cites

48 of 48 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Glycosylation of the synthetic peptide EA2 derived from Rattus norvegicus submandibular apomucin 10 (MUC10) has been demonstrated in various in vitro assays in the presence of soluble GalNAc-T2.

    “As an example, glycosylation of the synthetic peptide EA2 (PTTDSTTPAPTTK)—derived from Rattus norvegicus submandibular apomucin 10 (MUC10)—has been demonstrated in various in vitro assays in the presence of soluble GalNAc-T2 [6, 14, 15].”

    From High level in vivo mucin-type glycosylation in Escherichia coli (2018) · cites this paper as [15]

    The Experimental Procedures (page unavailable) describe an in vitro enzyme-activity assay using EA2, and Table 3 identifies EA2 as a peptide substrate of human GalNAc-T2. The paper gives the EA2 sequence, but the passages in our copy do not identify it as derived from Rattus norvegicus submandibular apomucin 10 (MUC10). (LLM, conf=0.84)

    Experimental — accuracy not yet measured

  • O-glycosylation of eukaryotic target sites using a truncated form of human GalNAc-T2 has been shown without altering the target peptide sequence.

    “In contrast, O-glycosylation of eukaryotic target sites using a truncated form of the human glycosyltransferase GalNAc-T2 has been shown without altering the target peptide sequence [6, 9, 14, 15].”

    From High level in vivo mucin-type glycosylation in Escherichia coli (2018) · cites this paper as [15]

  • Previous in vitro studies with GalNAc-T2 have identified Thr7 in the synthetic EA2 peptide sequence as a preferred glycosylation site.

    “Previous in vitro studies with GalNAc-T2 have identified Thr7 in the synthetic EA2 peptide sequence [14, 15] and Thr9 in the MUC5AC peptide as preferred glycosylation sites [31].”

    From High level in vivo mucin-type glycosylation in Escherichia coli (2018) · cites this paper as [15]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 5

  1. Rosen, S. D., Hwang, S. T., Giblin, P. A., and Singer, M. S. (1997) Biochem. Soc. Trans. 25, 428 -433
  2. Borsig, L., Wong, R., Feramisco, J., Nadeau, D. R., Varki, N. M., and Varki, A. (2001) Proc. Natl. Acad. Sci. U. S. A. 98, 3352-3357
  3. Hennet, T., Hagen, F. K., Tabak, L. A., and Marth, J. D. (1995) Proc. Natl. Acad. Sci.
  4. Fritz, T. A., Hurley, J. H., Trinh, L. B., Shiloach, J., and Tabak, L. A. (2004) Proc. Natl. Acad. Sci. U. S. A. 101, 15307-15312
  5. Shah, K., Liu, Y., Deirmengian, C., and Shokat, K. M. (1997) Proc. Natl. Acad. Sci.

Cited by

Sorted by citations

Related

Authors
Fritz, T. A., Raman, J., & Tabak, L. A.
Affiliations
National Institutes of Health (US)
Corresponding author
Tabak, Lawrence A.
ORCID
Tabak, Lawrence A.
Venue
Journal of Biological Chemistry
Publisher
Elsevier BV
Published
2006-03
Volume
281
Issue
13
Pages
8613-8619
ISSN
0021-9258 (ISSN-L)
DOI
10.1074/jbc.m513590200
OpenAlex
W1992607565
Cited by
163
References
48
Citations by year
2026: 1 · 2025: 6 · 2024: 14 · 2023: 3 · 2022: 4 · 2021: 5 · 2020: 10 · 2019: 10 · 2018: 8 · 2017: 6 · 2016: 10 · 2015: 5 · 2014: 11 · 2013: 6 · 2012: 6
FWCI
4.32
Type
journal article
Language
en
Update notices
erratum (2006-08-25)
Open access
Licence
Locations
  • Journal of Biological Chemistry (publishedVersion, cc-by)
  • PubMed (publishedVersion)
Funders
  • National Institutes of Health
  • National Institute of Diabetes and Digestive and Kidney Diseases
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Glycosylation and Glycoproteins Research
  • Physical Sciences › Chemistry › Organic Chemistry › Carbohydrate Chemistry and Synthesis
  • Physical Sciences › Materials Science › Materials Chemistry › Enzyme Structure and Function
Keywords
catalytic domain, lectin domain, domain flexibility, substrate recognition, acceptor substrate specificity, glycosylation sites
MeSH terms
Polypeptide N-acetylgalactosaminyltransferase, Amino Acid Sequence, Binding Sites, Glycosylation, Humans, Hydrogen Bonding, Isoenzymes, Kinetics, Manganese, Models, Molecular, Molecular Sequence Data, Protein Binding, Protein Conformation, Threonine, Uridine Diphosphate N-Acetylgalactosamine, Conserved Sequence, N-Acetylgalactosaminyltransferases, Protein Structure, Secondary, Protein Structure, Tertiary, Protein Folding, Crystallography, X-Ray, HL-60 Cells, Catalytic Domain, Lectins, Intracellular Signaling Peptides and Proteins, Hydrophobic and Hydrophilic Interactions

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review