The Ste5 Scaffold Directs Mating Signaling by Catalytically Unlocking the Fus3 MAP Kinase for Activation

Matthew Good, Grace Tang, Julie Singleton, A. Reményi, Wendell A. Lim

Research output: Contribution to journalArticle

122 Citations (Scopus)

Abstract

The scaffold protein Ste5 is required to properly direct signaling through the yeast mating pathway to the mitogen-activated protein kinase (MAPK), Fus3. Scaffolds are thought to function by tethering kinase and substrate in proximity. We find, however, that the previously identified Fus3-binding site on Ste5 is not required for signaling, suggesting an alternative mechanism controls Fus3's activation by the MAPKK Ste7. Reconstituting MAPK signaling in vitro, we find that Fus3 is an intrinsically poor substrate for Ste7, although the related filamentation MAPK, Kss1, is an excellent substrate. We identify and structurally characterize a domain in Ste5 that catalytically unlocks Fus3 for phosphorylation by Ste7. This domain selectively increases the kcat of Ste7→Fus3 phosphorylation but has no effect on Ste7→Kss1 phosphorylation. The dual requirement for both Ste7 and this Ste5 domain in Fus3 activation explains why Fus3 is selectively activated by the mating pathway and not by other pathways that also utilize Ste7.

Original languageEnglish
Pages (from-to)1085-1097
Number of pages13
JournalCell
Volume136
Issue number6
DOIs
Publication statusPublished - Mar 20 2009

Fingerprint

Phosphorylation
Mitogen-Activated Protein Kinases
Scaffolds
Phosphotransferases
Chemical activation
Substrates
Mitogen-Activated Protein Kinase Kinases
Yeast
Yeasts
Binding Sites
Proteins

Keywords

  • CELLBIO
  • PROTEINS
  • SIGNALING

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Cite this

The Ste5 Scaffold Directs Mating Signaling by Catalytically Unlocking the Fus3 MAP Kinase for Activation. / Good, Matthew; Tang, Grace; Singleton, Julie; Reményi, A.; Lim, Wendell A.

In: Cell, Vol. 136, No. 6, 20.03.2009, p. 1085-1097.

Research output: Contribution to journalArticle

Good, Matthew ; Tang, Grace ; Singleton, Julie ; Reményi, A. ; Lim, Wendell A. / The Ste5 Scaffold Directs Mating Signaling by Catalytically Unlocking the Fus3 MAP Kinase for Activation. In: Cell. 2009 ; Vol. 136, No. 6. pp. 1085-1097.
@article{e3641b7f01f942eab13720254ab5695b,
title = "The Ste5 Scaffold Directs Mating Signaling by Catalytically Unlocking the Fus3 MAP Kinase for Activation",
abstract = "The scaffold protein Ste5 is required to properly direct signaling through the yeast mating pathway to the mitogen-activated protein kinase (MAPK), Fus3. Scaffolds are thought to function by tethering kinase and substrate in proximity. We find, however, that the previously identified Fus3-binding site on Ste5 is not required for signaling, suggesting an alternative mechanism controls Fus3's activation by the MAPKK Ste7. Reconstituting MAPK signaling in vitro, we find that Fus3 is an intrinsically poor substrate for Ste7, although the related filamentation MAPK, Kss1, is an excellent substrate. We identify and structurally characterize a domain in Ste5 that catalytically unlocks Fus3 for phosphorylation by Ste7. This domain selectively increases the kcat of Ste7→Fus3 phosphorylation but has no effect on Ste7→Kss1 phosphorylation. The dual requirement for both Ste7 and this Ste5 domain in Fus3 activation explains why Fus3 is selectively activated by the mating pathway and not by other pathways that also utilize Ste7.",
keywords = "CELLBIO, PROTEINS, SIGNALING",
author = "Matthew Good and Grace Tang and Julie Singleton and A. Rem{\'e}nyi and Lim, {Wendell A.}",
year = "2009",
month = "3",
day = "20",
doi = "10.1016/j.cell.2009.01.049",
language = "English",
volume = "136",
pages = "1085--1097",
journal = "Cell",
issn = "0092-8674",
publisher = "Cell Press",
number = "6",

}

TY - JOUR

T1 - The Ste5 Scaffold Directs Mating Signaling by Catalytically Unlocking the Fus3 MAP Kinase for Activation

AU - Good, Matthew

AU - Tang, Grace

AU - Singleton, Julie

AU - Reményi, A.

AU - Lim, Wendell A.

PY - 2009/3/20

Y1 - 2009/3/20

N2 - The scaffold protein Ste5 is required to properly direct signaling through the yeast mating pathway to the mitogen-activated protein kinase (MAPK), Fus3. Scaffolds are thought to function by tethering kinase and substrate in proximity. We find, however, that the previously identified Fus3-binding site on Ste5 is not required for signaling, suggesting an alternative mechanism controls Fus3's activation by the MAPKK Ste7. Reconstituting MAPK signaling in vitro, we find that Fus3 is an intrinsically poor substrate for Ste7, although the related filamentation MAPK, Kss1, is an excellent substrate. We identify and structurally characterize a domain in Ste5 that catalytically unlocks Fus3 for phosphorylation by Ste7. This domain selectively increases the kcat of Ste7→Fus3 phosphorylation but has no effect on Ste7→Kss1 phosphorylation. The dual requirement for both Ste7 and this Ste5 domain in Fus3 activation explains why Fus3 is selectively activated by the mating pathway and not by other pathways that also utilize Ste7.

AB - The scaffold protein Ste5 is required to properly direct signaling through the yeast mating pathway to the mitogen-activated protein kinase (MAPK), Fus3. Scaffolds are thought to function by tethering kinase and substrate in proximity. We find, however, that the previously identified Fus3-binding site on Ste5 is not required for signaling, suggesting an alternative mechanism controls Fus3's activation by the MAPKK Ste7. Reconstituting MAPK signaling in vitro, we find that Fus3 is an intrinsically poor substrate for Ste7, although the related filamentation MAPK, Kss1, is an excellent substrate. We identify and structurally characterize a domain in Ste5 that catalytically unlocks Fus3 for phosphorylation by Ste7. This domain selectively increases the kcat of Ste7→Fus3 phosphorylation but has no effect on Ste7→Kss1 phosphorylation. The dual requirement for both Ste7 and this Ste5 domain in Fus3 activation explains why Fus3 is selectively activated by the mating pathway and not by other pathways that also utilize Ste7.

KW - CELLBIO

KW - PROTEINS

KW - SIGNALING

UR - http://www.scopus.com/inward/record.url?scp=62149128986&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=62149128986&partnerID=8YFLogxK

U2 - 10.1016/j.cell.2009.01.049

DO - 10.1016/j.cell.2009.01.049

M3 - Article

C2 - 19303851

AN - SCOPUS:62149128986

VL - 136

SP - 1085

EP - 1097

JO - Cell

JF - Cell

SN - 0092-8674

IS - 6

ER -