c-Myc is glycosylated at threonine 58, a known phosphorylation site and a mutational hot spot in lymphomas

T. Y. Chou, Gerald Warren Hart, C. V. Dang

Research output: Contribution to journalArticle

Abstract

c-Myc is a helix-loop-helix leucine zipper phosphoprotein that heterodimerizes with Max and regulates gene transcription in cell proliferation, cell differentiation, and programmed cell death. Previously, we demonstrated that c-Myc is modified by O-linked N-acetylglucosamine (O- GlcNAc) within or nearby the N-terminal transcriptional activation domain (Chou, T.-Y., Dang, C. V., and Hart, G. W. (1995) Proc. Natl. Acad. Sci. U.S.A. 92, 4417-4421). In this paper, we identified the O-GlcNAc attachment site(s) on c-Myc. c-Myc purified from sf9 insect cells was trypsinized, and its GlcNAc moieties were enzymically labeled with [3H]galactose. The [3H]galactose-labeled glycopeptides were isolated by reverse phase high performance liquid chromatography and then subjected to gas-phase sequencing, manual Edman degradation, and laser desorption/ionization mass spectrometry. These analyses show that threonine 58, an in vivo phosphorylation site in the transactivation domain, is the major O-GlcNAc glycosylation site of c-Myc. Mutation of threonine 58, frequently found in retroviral v-Myc proteins and in human Burkitt and AIDS-related lymphomas, is associated with enhanced transforming activity and tumorigenicity. The reciprocal glycosylation and phosphorylation at this biologically significant amino acid residue may play an important role in the regulation of the functions of c-Myc.

Original languageEnglish (US)
Pages (from-to)18961-18965
Number of pages5
JournalJournal of Biological Chemistry
Volume270
Issue number32
DOIs
StatePublished - 1995
Externally publishedYes

Fingerprint

Glycosylation
Phosphorylation
Threonine
Galactose
Transcriptional Activation
Lymphoma
AIDS-Related Lymphoma
Sf9 Cells
Leucine Zippers
Acetylglucosamine
Glycopeptides
Phosphoproteins
Cell proliferation
High performance liquid chromatography
Cell death
Reverse-Phase Chromatography
Transcription
Ionization
Mass spectrometry
Insects

ASJC Scopus subject areas

  • Biochemistry

Cite this

c-Myc is glycosylated at threonine 58, a known phosphorylation site and a mutational hot spot in lymphomas. / Chou, T. Y.; Hart, Gerald Warren; Dang, C. V.

In: Journal of Biological Chemistry, Vol. 270, No. 32, 1995, p. 18961-18965.

Research output: Contribution to journalArticle

Chou, T. Y. ; Hart, Gerald Warren ; Dang, C. V. / c-Myc is glycosylated at threonine 58, a known phosphorylation site and a mutational hot spot in lymphomas. In: Journal of Biological Chemistry. 1995 ; Vol. 270, No. 32. pp. 18961-18965.
@article{72663f49b7834b70aaa56b3b3cc13dd3,
title = "c-Myc is glycosylated at threonine 58, a known phosphorylation site and a mutational hot spot in lymphomas",
abstract = "c-Myc is a helix-loop-helix leucine zipper phosphoprotein that heterodimerizes with Max and regulates gene transcription in cell proliferation, cell differentiation, and programmed cell death. Previously, we demonstrated that c-Myc is modified by O-linked N-acetylglucosamine (O- GlcNAc) within or nearby the N-terminal transcriptional activation domain (Chou, T.-Y., Dang, C. V., and Hart, G. W. (1995) Proc. Natl. Acad. Sci. U.S.A. 92, 4417-4421). In this paper, we identified the O-GlcNAc attachment site(s) on c-Myc. c-Myc purified from sf9 insect cells was trypsinized, and its GlcNAc moieties were enzymically labeled with [3H]galactose. The [3H]galactose-labeled glycopeptides were isolated by reverse phase high performance liquid chromatography and then subjected to gas-phase sequencing, manual Edman degradation, and laser desorption/ionization mass spectrometry. These analyses show that threonine 58, an in vivo phosphorylation site in the transactivation domain, is the major O-GlcNAc glycosylation site of c-Myc. Mutation of threonine 58, frequently found in retroviral v-Myc proteins and in human Burkitt and AIDS-related lymphomas, is associated with enhanced transforming activity and tumorigenicity. The reciprocal glycosylation and phosphorylation at this biologically significant amino acid residue may play an important role in the regulation of the functions of c-Myc.",
author = "Chou, {T. Y.} and Hart, {Gerald Warren} and Dang, {C. V.}",
year = "1995",
doi = "10.1074/jbc.270.32.18961",
language = "English (US)",
volume = "270",
pages = "18961--18965",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "32",

}

TY - JOUR

T1 - c-Myc is glycosylated at threonine 58, a known phosphorylation site and a mutational hot spot in lymphomas

AU - Chou, T. Y.

AU - Hart, Gerald Warren

AU - Dang, C. V.

PY - 1995

Y1 - 1995

N2 - c-Myc is a helix-loop-helix leucine zipper phosphoprotein that heterodimerizes with Max and regulates gene transcription in cell proliferation, cell differentiation, and programmed cell death. Previously, we demonstrated that c-Myc is modified by O-linked N-acetylglucosamine (O- GlcNAc) within or nearby the N-terminal transcriptional activation domain (Chou, T.-Y., Dang, C. V., and Hart, G. W. (1995) Proc. Natl. Acad. Sci. U.S.A. 92, 4417-4421). In this paper, we identified the O-GlcNAc attachment site(s) on c-Myc. c-Myc purified from sf9 insect cells was trypsinized, and its GlcNAc moieties were enzymically labeled with [3H]galactose. The [3H]galactose-labeled glycopeptides were isolated by reverse phase high performance liquid chromatography and then subjected to gas-phase sequencing, manual Edman degradation, and laser desorption/ionization mass spectrometry. These analyses show that threonine 58, an in vivo phosphorylation site in the transactivation domain, is the major O-GlcNAc glycosylation site of c-Myc. Mutation of threonine 58, frequently found in retroviral v-Myc proteins and in human Burkitt and AIDS-related lymphomas, is associated with enhanced transforming activity and tumorigenicity. The reciprocal glycosylation and phosphorylation at this biologically significant amino acid residue may play an important role in the regulation of the functions of c-Myc.

AB - c-Myc is a helix-loop-helix leucine zipper phosphoprotein that heterodimerizes with Max and regulates gene transcription in cell proliferation, cell differentiation, and programmed cell death. Previously, we demonstrated that c-Myc is modified by O-linked N-acetylglucosamine (O- GlcNAc) within or nearby the N-terminal transcriptional activation domain (Chou, T.-Y., Dang, C. V., and Hart, G. W. (1995) Proc. Natl. Acad. Sci. U.S.A. 92, 4417-4421). In this paper, we identified the O-GlcNAc attachment site(s) on c-Myc. c-Myc purified from sf9 insect cells was trypsinized, and its GlcNAc moieties were enzymically labeled with [3H]galactose. The [3H]galactose-labeled glycopeptides were isolated by reverse phase high performance liquid chromatography and then subjected to gas-phase sequencing, manual Edman degradation, and laser desorption/ionization mass spectrometry. These analyses show that threonine 58, an in vivo phosphorylation site in the transactivation domain, is the major O-GlcNAc glycosylation site of c-Myc. Mutation of threonine 58, frequently found in retroviral v-Myc proteins and in human Burkitt and AIDS-related lymphomas, is associated with enhanced transforming activity and tumorigenicity. The reciprocal glycosylation and phosphorylation at this biologically significant amino acid residue may play an important role in the regulation of the functions of c-Myc.

UR - http://www.scopus.com/inward/record.url?scp=0029049198&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029049198&partnerID=8YFLogxK

U2 - 10.1074/jbc.270.32.18961

DO - 10.1074/jbc.270.32.18961

M3 - Article

C2 - 7642555

AN - SCOPUS:0029049198

VL - 270

SP - 18961

EP - 18965

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 32

ER -