Membrane fusion triggering

Three modules with different structure and function in the upper half of the measles virus attachment protein stalk

Chanakha K. Navaratnarajah, Surendra Negi, Werner Braun, Roberto Cattaneo

Research output: Contribution to journalArticle

36 Citations (Scopus)

Abstract

The measles virus (MV) fusion apparatus consists of a fusion protein and an attachment protein named hemagglutinin (H). After receptor-binding through its cuboidal head, the H-protein transmits the fusion-triggering signal through its stalk to the fusion protein. However, the structural basis of signal transmission is unclear because only structures of H-heads without their stalk have been solved. On the other hand, the entire ectodomain structure of the hemagglutinin-neuraminidase protein of another Paramyxovirus revealed a four-helix bundle stalk. To probe the structure of the 95-residue MV H-stalk we individually substituted head-proximal residues (positions 103-153) with cysteine, and biochemically and functionally characterized the resultant proteins. Our results indicate that most residues in the central segment (positions 103-117) can be cross-linked by engineered disulfide bonds, and thus may be engaged in a tetrameric structure. While covalent tetramerization disrupts fusion triggering function, disulfide bond reduction restores it in most positions except Asp-113. The next stalk segment (residues 123-138) also has high propensity to form covalent tetramers, but since these cross-links have little or no effect on function, it can conduct the fusion-triggering signal while remaining in a stabilized tetrameric configuration. This segment may act as a spacer, maintaining H-heads at an optimal height. Finally, the head-proximal segment (residues 139-154) has very limited propensity to trap tetramers, suggesting bifurcation into two flexible linkers clamped by inter-subunit covalent links formed by natural Cys-139 and Cys-154. We discuss the modular structure of the MV H-stalk in the context of membrane fusion triggering and cell entry by Paramyxoviruses.

Original languageEnglish (US)
Pages (from-to)38543-38551
Number of pages9
JournalJournal of Biological Chemistry
Volume287
Issue number46
DOIs
StatePublished - Nov 9 2012

Fingerprint

Virus Attachment
Measles virus
Membrane Fusion
Viruses
Fusion reactions
Membranes
Head
Proteins
Hemagglutinins
Disulfides
Neuraminidase
Cysteine

ASJC Scopus subject areas

  • Biochemistry
  • Cell Biology
  • Molecular Biology

Cite this

Membrane fusion triggering : Three modules with different structure and function in the upper half of the measles virus attachment protein stalk. / Navaratnarajah, Chanakha K.; Negi, Surendra; Braun, Werner; Cattaneo, Roberto.

In: Journal of Biological Chemistry, Vol. 287, No. 46, 09.11.2012, p. 38543-38551.

Research output: Contribution to journalArticle

@article{ae63e24b435d40e0a1e5a50f23dceda9,
title = "Membrane fusion triggering: Three modules with different structure and function in the upper half of the measles virus attachment protein stalk",
abstract = "The measles virus (MV) fusion apparatus consists of a fusion protein and an attachment protein named hemagglutinin (H). After receptor-binding through its cuboidal head, the H-protein transmits the fusion-triggering signal through its stalk to the fusion protein. However, the structural basis of signal transmission is unclear because only structures of H-heads without their stalk have been solved. On the other hand, the entire ectodomain structure of the hemagglutinin-neuraminidase protein of another Paramyxovirus revealed a four-helix bundle stalk. To probe the structure of the 95-residue MV H-stalk we individually substituted head-proximal residues (positions 103-153) with cysteine, and biochemically and functionally characterized the resultant proteins. Our results indicate that most residues in the central segment (positions 103-117) can be cross-linked by engineered disulfide bonds, and thus may be engaged in a tetrameric structure. While covalent tetramerization disrupts fusion triggering function, disulfide bond reduction restores it in most positions except Asp-113. The next stalk segment (residues 123-138) also has high propensity to form covalent tetramers, but since these cross-links have little or no effect on function, it can conduct the fusion-triggering signal while remaining in a stabilized tetrameric configuration. This segment may act as a spacer, maintaining H-heads at an optimal height. Finally, the head-proximal segment (residues 139-154) has very limited propensity to trap tetramers, suggesting bifurcation into two flexible linkers clamped by inter-subunit covalent links formed by natural Cys-139 and Cys-154. We discuss the modular structure of the MV H-stalk in the context of membrane fusion triggering and cell entry by Paramyxoviruses.",
author = "Navaratnarajah, {Chanakha K.} and Surendra Negi and Werner Braun and Roberto Cattaneo",
year = "2012",
month = "11",
day = "9",
doi = "10.1074/jbc.M112.410563",
language = "English (US)",
volume = "287",
pages = "38543--38551",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "46",

}

TY - JOUR

T1 - Membrane fusion triggering

T2 - Three modules with different structure and function in the upper half of the measles virus attachment protein stalk

AU - Navaratnarajah, Chanakha K.

AU - Negi, Surendra

AU - Braun, Werner

AU - Cattaneo, Roberto

PY - 2012/11/9

Y1 - 2012/11/9

N2 - The measles virus (MV) fusion apparatus consists of a fusion protein and an attachment protein named hemagglutinin (H). After receptor-binding through its cuboidal head, the H-protein transmits the fusion-triggering signal through its stalk to the fusion protein. However, the structural basis of signal transmission is unclear because only structures of H-heads without their stalk have been solved. On the other hand, the entire ectodomain structure of the hemagglutinin-neuraminidase protein of another Paramyxovirus revealed a four-helix bundle stalk. To probe the structure of the 95-residue MV H-stalk we individually substituted head-proximal residues (positions 103-153) with cysteine, and biochemically and functionally characterized the resultant proteins. Our results indicate that most residues in the central segment (positions 103-117) can be cross-linked by engineered disulfide bonds, and thus may be engaged in a tetrameric structure. While covalent tetramerization disrupts fusion triggering function, disulfide bond reduction restores it in most positions except Asp-113. The next stalk segment (residues 123-138) also has high propensity to form covalent tetramers, but since these cross-links have little or no effect on function, it can conduct the fusion-triggering signal while remaining in a stabilized tetrameric configuration. This segment may act as a spacer, maintaining H-heads at an optimal height. Finally, the head-proximal segment (residues 139-154) has very limited propensity to trap tetramers, suggesting bifurcation into two flexible linkers clamped by inter-subunit covalent links formed by natural Cys-139 and Cys-154. We discuss the modular structure of the MV H-stalk in the context of membrane fusion triggering and cell entry by Paramyxoviruses.

AB - The measles virus (MV) fusion apparatus consists of a fusion protein and an attachment protein named hemagglutinin (H). After receptor-binding through its cuboidal head, the H-protein transmits the fusion-triggering signal through its stalk to the fusion protein. However, the structural basis of signal transmission is unclear because only structures of H-heads without their stalk have been solved. On the other hand, the entire ectodomain structure of the hemagglutinin-neuraminidase protein of another Paramyxovirus revealed a four-helix bundle stalk. To probe the structure of the 95-residue MV H-stalk we individually substituted head-proximal residues (positions 103-153) with cysteine, and biochemically and functionally characterized the resultant proteins. Our results indicate that most residues in the central segment (positions 103-117) can be cross-linked by engineered disulfide bonds, and thus may be engaged in a tetrameric structure. While covalent tetramerization disrupts fusion triggering function, disulfide bond reduction restores it in most positions except Asp-113. The next stalk segment (residues 123-138) also has high propensity to form covalent tetramers, but since these cross-links have little or no effect on function, it can conduct the fusion-triggering signal while remaining in a stabilized tetrameric configuration. This segment may act as a spacer, maintaining H-heads at an optimal height. Finally, the head-proximal segment (residues 139-154) has very limited propensity to trap tetramers, suggesting bifurcation into two flexible linkers clamped by inter-subunit covalent links formed by natural Cys-139 and Cys-154. We discuss the modular structure of the MV H-stalk in the context of membrane fusion triggering and cell entry by Paramyxoviruses.

UR - http://www.scopus.com/inward/record.url?scp=84869027005&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84869027005&partnerID=8YFLogxK

U2 - 10.1074/jbc.M112.410563

DO - 10.1074/jbc.M112.410563

M3 - Article

VL - 287

SP - 38543

EP - 38551

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 46

ER -