Molecular interactions position Mso1p, a novel PTB domain homologue, in the interface of the exocyst complex and the exocytic SNARE machinery in yeast

Michael Knop (Corresponding Author), K. Juha Miller, Massimiliano Mazza, DeJiang Feng, Marion Weber, Sirkka Keränen, Jussi Jäntti (Corresponding Author)

Research output: Contribution to journalArticleScientificpeer-review

24 Citations (Scopus)

Abstract

In this study, we have analyzed the association of the Sec1p interacting protein Mso1p with the membrane fusion machinery in yeast. We show that Mso1p is essential for vesicle fusion during prospore membrane formation. Green fluorescent protein-tagged Mso1p localizes to the sites of exocytosis and at the site of prospore membrane formation. In vivo and in vitro experiments identified a short amino-terminal sequence in Mso1p that mediates its interaction with Sec1p and is needed for vesicle fusion. A point mutation, T47A, within the Sec1p-binding domain abolishes Mso1p functionality in vivo, and mso1T47A mutant cells display specific genetic interactions with sec1 mutants. Mso1p coimmunoprecipitates with Sec1p, Sso1/2p, Snc1/2p, Sec9p, and the exocyst complex subunit Sec15p. In sec4-8 and SEC4I133 mutant cells, association of Mso1p with Sso1/2p, Snc1/2p, and Sec9p is affected, whereas interaction with Sec1p persists. Furthermore, in SEC4I133 cells the dominant negative Sec4I133p coimmunoprecipitates with Mso1p–Sec1p complex. Finally, we identify Mso1p as a homologue of the PTB binding domain of the mammalian Sec1p binding Mint proteins. These results position Mso1p in the interface of the exocyst complex, Sec4p, and the SNARE machinery, and reveal a novel layer of molecular conservation in the exocytosis machinery.
Original languageEnglish
Pages (from-to)4543 - 4556
Number of pages14
JournalMolecular Biology of the Cell
Volume16
Issue number10
DOIs
Publication statusPublished - 2005
MoE publication typeA1 Journal article-refereed

Fingerprint

SNARE Proteins
Yeasts
Exocytosis
Mentha
Membrane Fusion
Membranes
Green Fluorescent Proteins
Point Mutation
Carrier Proteins
Proteins

Keywords

  • yeasts
  • SNARE
  • SNARE proteins
  • proteins
  • exocyst
  • exocyst complexes

Cite this

Knop, Michael ; Miller, K. Juha ; Mazza, Massimiliano ; Feng, DeJiang ; Weber, Marion ; Keränen, Sirkka ; Jäntti, Jussi. / Molecular interactions position Mso1p, a novel PTB domain homologue, in the interface of the exocyst complex and the exocytic SNARE machinery in yeast. In: Molecular Biology of the Cell. 2005 ; Vol. 16, No. 10. pp. 4543 - 4556.
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title = "Molecular interactions position Mso1p, a novel PTB domain homologue, in the interface of the exocyst complex and the exocytic SNARE machinery in yeast",
abstract = "In this study, we have analyzed the association of the Sec1p interacting protein Mso1p with the membrane fusion machinery in yeast. We show that Mso1p is essential for vesicle fusion during prospore membrane formation. Green fluorescent protein-tagged Mso1p localizes to the sites of exocytosis and at the site of prospore membrane formation. In vivo and in vitro experiments identified a short amino-terminal sequence in Mso1p that mediates its interaction with Sec1p and is needed for vesicle fusion. A point mutation, T47A, within the Sec1p-binding domain abolishes Mso1p functionality in vivo, and mso1T47A mutant cells display specific genetic interactions with sec1 mutants. Mso1p coimmunoprecipitates with Sec1p, Sso1/2p, Snc1/2p, Sec9p, and the exocyst complex subunit Sec15p. In sec4-8 and SEC4I133 mutant cells, association of Mso1p with Sso1/2p, Snc1/2p, and Sec9p is affected, whereas interaction with Sec1p persists. Furthermore, in SEC4I133 cells the dominant negative Sec4I133p coimmunoprecipitates with Mso1p–Sec1p complex. Finally, we identify Mso1p as a homologue of the PTB binding domain of the mammalian Sec1p binding Mint proteins. These results position Mso1p in the interface of the exocyst complex, Sec4p, and the SNARE machinery, and reveal a novel layer of molecular conservation in the exocytosis machinery.",
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Molecular interactions position Mso1p, a novel PTB domain homologue, in the interface of the exocyst complex and the exocytic SNARE machinery in yeast. / Knop, Michael (Corresponding Author); Miller, K. Juha; Mazza, Massimiliano; Feng, DeJiang; Weber, Marion; Keränen, Sirkka; Jäntti, Jussi (Corresponding Author).

In: Molecular Biology of the Cell, Vol. 16, No. 10, 2005, p. 4543 - 4556.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Molecular interactions position Mso1p, a novel PTB domain homologue, in the interface of the exocyst complex and the exocytic SNARE machinery in yeast

AU - Knop, Michael

AU - Miller, K. Juha

AU - Mazza, Massimiliano

AU - Feng, DeJiang

AU - Weber, Marion

AU - Keränen, Sirkka

AU - Jäntti, Jussi

PY - 2005

Y1 - 2005

N2 - In this study, we have analyzed the association of the Sec1p interacting protein Mso1p with the membrane fusion machinery in yeast. We show that Mso1p is essential for vesicle fusion during prospore membrane formation. Green fluorescent protein-tagged Mso1p localizes to the sites of exocytosis and at the site of prospore membrane formation. In vivo and in vitro experiments identified a short amino-terminal sequence in Mso1p that mediates its interaction with Sec1p and is needed for vesicle fusion. A point mutation, T47A, within the Sec1p-binding domain abolishes Mso1p functionality in vivo, and mso1T47A mutant cells display specific genetic interactions with sec1 mutants. Mso1p coimmunoprecipitates with Sec1p, Sso1/2p, Snc1/2p, Sec9p, and the exocyst complex subunit Sec15p. In sec4-8 and SEC4I133 mutant cells, association of Mso1p with Sso1/2p, Snc1/2p, and Sec9p is affected, whereas interaction with Sec1p persists. Furthermore, in SEC4I133 cells the dominant negative Sec4I133p coimmunoprecipitates with Mso1p–Sec1p complex. Finally, we identify Mso1p as a homologue of the PTB binding domain of the mammalian Sec1p binding Mint proteins. These results position Mso1p in the interface of the exocyst complex, Sec4p, and the SNARE machinery, and reveal a novel layer of molecular conservation in the exocytosis machinery.

AB - In this study, we have analyzed the association of the Sec1p interacting protein Mso1p with the membrane fusion machinery in yeast. We show that Mso1p is essential for vesicle fusion during prospore membrane formation. Green fluorescent protein-tagged Mso1p localizes to the sites of exocytosis and at the site of prospore membrane formation. In vivo and in vitro experiments identified a short amino-terminal sequence in Mso1p that mediates its interaction with Sec1p and is needed for vesicle fusion. A point mutation, T47A, within the Sec1p-binding domain abolishes Mso1p functionality in vivo, and mso1T47A mutant cells display specific genetic interactions with sec1 mutants. Mso1p coimmunoprecipitates with Sec1p, Sso1/2p, Snc1/2p, Sec9p, and the exocyst complex subunit Sec15p. In sec4-8 and SEC4I133 mutant cells, association of Mso1p with Sso1/2p, Snc1/2p, and Sec9p is affected, whereas interaction with Sec1p persists. Furthermore, in SEC4I133 cells the dominant negative Sec4I133p coimmunoprecipitates with Mso1p–Sec1p complex. Finally, we identify Mso1p as a homologue of the PTB binding domain of the mammalian Sec1p binding Mint proteins. These results position Mso1p in the interface of the exocyst complex, Sec4p, and the SNARE machinery, and reveal a novel layer of molecular conservation in the exocytosis machinery.

KW - yeasts

KW - SNARE

KW - SNARE proteins

KW - proteins

KW - exocyst

KW - exocyst complexes

U2 - 10.1091/mbc.E05-03-0243

DO - 10.1091/mbc.E05-03-0243

M3 - Article

VL - 16

SP - 4543

EP - 4556

JO - Molecular Biology of the Cell

JF - Molecular Biology of the Cell

SN - 1059-1524

IS - 10

ER -