A CapG gain-of-function mutant reveals critical structural and functional determinants for actin filament severing

Y. Zhang, Sergey M. Vorobiev, Bruce G. Gibson, Binghua Hao, Gurjit S. Sidhu, Vishnu S. Mishra, Elena G. Yarmola, Michael R. Bubb, Steven C. Almo, Frederick S. Southwick

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

CapG is the only member of the gelsolin family unable to sever actin filaments. Changing amino acids 84-91 (severing domain) and 124-137 (WH2-containing segment) simultaneously to the sequences of gelsolin results in a mutant, CapG-sev, capable of severing actin filaments. The gain of severing function does not alter actin filament capping, but is accompanied by a higher affinity for monomeric actin, and the capacity to bind and sequester two actin monomers. Analysis of CapG-sev crystal structure suggests a more loosely folded inactive conformation than gelsolin, with a shorter S1-S2 latch. Calcium binding to S1 opens this latch and S1 becomes separated from a closely interfaced S2-S3 complex by an extended arm consisting of amino acids 118-137. Modeling with F-actin predicts that the length of this WH2-containing arm is critical for severing function, and the addition of a single amino acid (alanine or histidine) eliminates CapG-sev severing activity, confirming this prediction. We conclude that efficient severing utilizes two actin monomer-binding sites, and that the length of the WH2-containing segment is a critical functional determinant for severing.

Original languageEnglish (US)
Pages (from-to)4458-4467
Number of pages10
JournalEMBO Journal
Volume25
Issue number19
DOIs
StatePublished - Oct 4 2006

Fingerprint

Gelsolin
Actin Cytoskeleton
Actins
Amino Acids
Histidine
Alanine
Monomers
Binding Sites
Calcium
Conformations
Crystal structure

Keywords

  • Actin-regulatory proteins
  • CapG
  • Gelsolin
  • Severing
  • WH2

ASJC Scopus subject areas

  • Genetics
  • Cell Biology

Cite this

Zhang, Y., Vorobiev, S. M., Gibson, B. G., Hao, B., Sidhu, G. S., Mishra, V. S., ... Southwick, F. S. (2006). A CapG gain-of-function mutant reveals critical structural and functional determinants for actin filament severing. EMBO Journal, 25(19), 4458-4467. https://doi.org/10.1038/sj.emboj.7601323

A CapG gain-of-function mutant reveals critical structural and functional determinants for actin filament severing. / Zhang, Y.; Vorobiev, Sergey M.; Gibson, Bruce G.; Hao, Binghua; Sidhu, Gurjit S.; Mishra, Vishnu S.; Yarmola, Elena G.; Bubb, Michael R.; Almo, Steven C.; Southwick, Frederick S.

In: EMBO Journal, Vol. 25, No. 19, 04.10.2006, p. 4458-4467.

Research output: Contribution to journalArticle

Zhang, Y, Vorobiev, SM, Gibson, BG, Hao, B, Sidhu, GS, Mishra, VS, Yarmola, EG, Bubb, MR, Almo, SC & Southwick, FS 2006, 'A CapG gain-of-function mutant reveals critical structural and functional determinants for actin filament severing', EMBO Journal, vol. 25, no. 19, pp. 4458-4467. https://doi.org/10.1038/sj.emboj.7601323
Zhang, Y. ; Vorobiev, Sergey M. ; Gibson, Bruce G. ; Hao, Binghua ; Sidhu, Gurjit S. ; Mishra, Vishnu S. ; Yarmola, Elena G. ; Bubb, Michael R. ; Almo, Steven C. ; Southwick, Frederick S. / A CapG gain-of-function mutant reveals critical structural and functional determinants for actin filament severing. In: EMBO Journal. 2006 ; Vol. 25, No. 19. pp. 4458-4467.
@article{63f8e62f25094a22a917bff7b20bee46,
title = "A CapG gain-of-function mutant reveals critical structural and functional determinants for actin filament severing",
abstract = "CapG is the only member of the gelsolin family unable to sever actin filaments. Changing amino acids 84-91 (severing domain) and 124-137 (WH2-containing segment) simultaneously to the sequences of gelsolin results in a mutant, CapG-sev, capable of severing actin filaments. The gain of severing function does not alter actin filament capping, but is accompanied by a higher affinity for monomeric actin, and the capacity to bind and sequester two actin monomers. Analysis of CapG-sev crystal structure suggests a more loosely folded inactive conformation than gelsolin, with a shorter S1-S2 latch. Calcium binding to S1 opens this latch and S1 becomes separated from a closely interfaced S2-S3 complex by an extended arm consisting of amino acids 118-137. Modeling with F-actin predicts that the length of this WH2-containing arm is critical for severing function, and the addition of a single amino acid (alanine or histidine) eliminates CapG-sev severing activity, confirming this prediction. We conclude that efficient severing utilizes two actin monomer-binding sites, and that the length of the WH2-containing segment is a critical functional determinant for severing.",
keywords = "Actin-regulatory proteins, CapG, Gelsolin, Severing, WH2",
author = "Y. Zhang and Vorobiev, {Sergey M.} and Gibson, {Bruce G.} and Binghua Hao and Sidhu, {Gurjit S.} and Mishra, {Vishnu S.} and Yarmola, {Elena G.} and Bubb, {Michael R.} and Almo, {Steven C.} and Southwick, {Frederick S.}",
year = "2006",
month = "10",
day = "4",
doi = "10.1038/sj.emboj.7601323",
language = "English (US)",
volume = "25",
pages = "4458--4467",
journal = "EMBO Journal",
issn = "0261-4189",
publisher = "Nature Publishing Group",
number = "19",

}

TY - JOUR

T1 - A CapG gain-of-function mutant reveals critical structural and functional determinants for actin filament severing

AU - Zhang, Y.

AU - Vorobiev, Sergey M.

AU - Gibson, Bruce G.

AU - Hao, Binghua

AU - Sidhu, Gurjit S.

AU - Mishra, Vishnu S.

AU - Yarmola, Elena G.

AU - Bubb, Michael R.

AU - Almo, Steven C.

AU - Southwick, Frederick S.

PY - 2006/10/4

Y1 - 2006/10/4

N2 - CapG is the only member of the gelsolin family unable to sever actin filaments. Changing amino acids 84-91 (severing domain) and 124-137 (WH2-containing segment) simultaneously to the sequences of gelsolin results in a mutant, CapG-sev, capable of severing actin filaments. The gain of severing function does not alter actin filament capping, but is accompanied by a higher affinity for monomeric actin, and the capacity to bind and sequester two actin monomers. Analysis of CapG-sev crystal structure suggests a more loosely folded inactive conformation than gelsolin, with a shorter S1-S2 latch. Calcium binding to S1 opens this latch and S1 becomes separated from a closely interfaced S2-S3 complex by an extended arm consisting of amino acids 118-137. Modeling with F-actin predicts that the length of this WH2-containing arm is critical for severing function, and the addition of a single amino acid (alanine or histidine) eliminates CapG-sev severing activity, confirming this prediction. We conclude that efficient severing utilizes two actin monomer-binding sites, and that the length of the WH2-containing segment is a critical functional determinant for severing.

AB - CapG is the only member of the gelsolin family unable to sever actin filaments. Changing amino acids 84-91 (severing domain) and 124-137 (WH2-containing segment) simultaneously to the sequences of gelsolin results in a mutant, CapG-sev, capable of severing actin filaments. The gain of severing function does not alter actin filament capping, but is accompanied by a higher affinity for monomeric actin, and the capacity to bind and sequester two actin monomers. Analysis of CapG-sev crystal structure suggests a more loosely folded inactive conformation than gelsolin, with a shorter S1-S2 latch. Calcium binding to S1 opens this latch and S1 becomes separated from a closely interfaced S2-S3 complex by an extended arm consisting of amino acids 118-137. Modeling with F-actin predicts that the length of this WH2-containing arm is critical for severing function, and the addition of a single amino acid (alanine or histidine) eliminates CapG-sev severing activity, confirming this prediction. We conclude that efficient severing utilizes two actin monomer-binding sites, and that the length of the WH2-containing segment is a critical functional determinant for severing.

KW - Actin-regulatory proteins

KW - CapG

KW - Gelsolin

KW - Severing

KW - WH2

UR - http://www.scopus.com/inward/record.url?scp=33749320277&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33749320277&partnerID=8YFLogxK

U2 - 10.1038/sj.emboj.7601323

DO - 10.1038/sj.emboj.7601323

M3 - Article

C2 - 16977317

AN - SCOPUS:33749320277

VL - 25

SP - 4458

EP - 4467

JO - EMBO Journal

JF - EMBO Journal

SN - 0261-4189

IS - 19

ER -