Effect of sphingomyelin and cholesterol on the interaction of St II with lipidic interfaces

Martínez, Diana; Otero, Anselmo; Álvarez, Carlos; Pazos, Fabiola; Tejuca, Mayra; Lanio, María E.; Gutiérrez-Aguirre, Ion; Barlič, Ariana; Iloro, Ibón; Arrondo, José Luis R.; González-Mañas, Juan Manuel; Lissi, E. A.

doi:10.1016/j.toxicon.2006.09.019

Cited by 59 publications

(56 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This activity is strongly dependent on the lipid composition of the membrane favored by the presence of SM, cholesterol and non-bilayer-forming lipids (Alvarez-Valcarcel et al 2001;Alvarez et al 2003;Martinez et al 2007;Pedrera et al 2015). In turn, this activity modifies the membrane properties by promoting the mixing of the lipid phases and an increase in the order of the system; therefore, the interaction of Sts with lipids entails a remodeling of membrane domains that probably facilitates the action of the toxin (Ros et al 2013).…”

Section: The Pore Architecture Of Actinoporinsmentioning

confidence: 99%

“…In the second method, which is the more employed of the two, the area is kept constant and the increase in π that is produced by injecting the protein into the subphase is measured, as a function of time, until equilibrium is reached (Brockman 1999;Maget-Dana 1999). Monolayers have been used to study the membrane binding of diverse families of proteins, such as lipolytic toxins (Maget-Dana 1999), some cell transcription factors, myelin protein components (Maggio et al 2008), sphingomyelinases (Fanani et al 2010) and several members of the actinoporin family (Barlic et al 2004;Bellomio et al 2009) including Sts (Martinez et al 2007;Pedrera et al 2014Pedrera et al , 2015. On the other hand, liposomal vesicles are the most accepted systems as membrane models due to their bilayer organization and vesicular geometry.…”

Section: Understanding the Interaction Of Actinoporins With Membranesmentioning

confidence: 99%

“…It appears that actinoporins recognize SM both at the level of the headgroup and at the ceramide (Cer) moiety (Alvarez et al 2009;Soto et al 2017). SM strongly promotes irreversible binding and pore formation in model membranes (Alvarez-Valcarcel et al 2001;Martinez et al 2007). In general, SM not only acts as a lipid receptor of actinoporins on the membrane surface, but also as a structural element of the pore, where it plays the role of an assembly co-factor (Tanaka et al 2015).…”

Section: Membrane Physico-chemical Requirements For the Binding And Amentioning

confidence: 99%

“…Although the joint presence of SM and Chol in membranes significantly increases the binding and permeabilizing activity of actinoporins, this enhancement has been related to the coexistence of lipid phases (Barlic et al 2004;Martinez et al 2007;Schon et al 2008;Rojko et al 2014;GarciaLinares et al 2015). In model membrane systems, the liquid ordered (Lo) domains occur usually when Chol associates with saturated glycerophospholipids or sphingophospholipids to render phospholipid-Chol complexes.…”

Section: Cholesterol and Other Sterolsmentioning

confidence: 99%

“…In particular, SM has emerged as the major partner of Chol for Lo phase formation, and ternary mixtures of dioleoylphosphatidylcholine (DOPC), SM and Chol are the most widely studied systems used to characterize the Lo/liquid-disordered (Ld) phase coexistence (de Almeida et al 2003). In this regard, the influence of Lo/Ld phase coexistence in bilayers and their equivalent Lo and liquid-expanded phases in monolayers have been the most studied systems in the actinoporin family (Barlic et al 2004;Martinez et al 2007;Schon et al 2008;Rojko et al 2014;Garcia-Linares et al 2015). For example, lateral defects related to the presence of Lo domains have been considered the preferential binding sites for EqtII (de Almeida et al 2003;Barlic et al 2004).…”

Section: Cholesterol and Other Sterolsmentioning

confidence: 99%

See 4 more Smart Citations

Biophysical and biochemical strategies to understand membrane binding and pore formation by sticholysins, pore-forming proteins from a sea anemone

et al. 2017

Self Cite

View full text Add to dashboard Cite

Actinoporins constitute a unique class of poreforming toxins found in sea anemones that are able to bind and oligomerize in membranes, leading to cell swelling, impairment of ionic gradients and, eventually, to cell death. In this review we summarize the knowledge generated from the combination of biochemical and biophysical approaches to the study of sticholysins I and II (Sts, StI/II), two actinoporins largely characterized by the Center of Protein Studies at the University of Havana during the last 20 years. These approaches include strategies for understanding the toxin structure-function relationship, the protein-membrane association process leading to pore formation and the interaction of toxin with cells. The rational combination of experimental and theoretical tools have allowed unraveling, at least partially, of the complex mechanisms involved in toxin-membrane interaction and of the molecular pathways triggered upon this interaction. The study of actinoporins is important not only to gain an understanding of their biological roles in anemone venom but also to investigate basic molecular mechanisms of protein insertion into membranes, protein-lipid interactions and the modulation of protein conformation by lipid binding. A deeper knowledge of the basic molecular mechanisms involved in Sts-cell interaction, as described in this review, will support the current investigations conducted by our group which focus on the design of immunotoxins against tumor cells and antigen-releasing systems to cell cytosol as Stsbased vaccine platforms.

show abstract

Section: The Pore Architecture Of Actinoporinsmentioning

confidence: 99%

Section: Understanding the Interaction Of Actinoporins With Membranesmentioning

confidence: 99%

Section: Membrane Physico-chemical Requirements For the Binding And Amentioning

confidence: 99%

Section: Cholesterol and Other Sterolsmentioning

confidence: 99%

Section: Cholesterol and Other Sterolsmentioning

confidence: 99%

See 3 more Smart Citations

Biophysical and biochemical strategies to understand membrane binding and pore formation by sticholysins, pore-forming proteins from a sea anemone

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

Photobleaching Reveals Heterogeneous Stoichiometry for Equinatoxin II Oligomers

et al. 2014

View full text Add to dashboard Cite

Equinatoxin II (EqtII), a sea anemone cytolysin, is known to oligomerize to form pores that spontaneously insert into membranes. Crystallographic and cryo-EM studies of structurally similar cytolysins offer contradictory evidence for pore stoichiometry. Here we used single-molecule photobleaching of fluorescently labeled EqtII to determine the stoichiometry of EqtII oligomers in supported lipid bilayers. A frequency analysis of photobleaching steps revealed a log-normal distribution of stoichiometries with a mean of 3.4±2.3 standard deviations. Comparison of our experimental data with simulations of fixed stoichiometries supports our observation of a heterogeneous distribution of EqtII oligomerization. These data are consistent with a model of EqtII stoichiometry where pores are on average tetrameric, but with large variation in the number of subunits in individual pores.

show abstract

Disrupting a key hydrophobic pair in the oligomerization interface of the actinoporins impairs their pore‐forming activity

et al. 2017

Self Cite

View full text Add to dashboard Cite

Crystallographic data of the dimeric and octameric forms of fragaceatoxin C (FraC) suggested the key role of a small hydrophobic protein-protein interaction surface for actinoporins oligomerization and pore formation in membranes. However, site-directed mutagenesis studies supporting this hypothesis for others actinoporins are still lacking. Here, we demonstrate that disrupting the key hydrophobic interaction between V60 and F163 (FraC numbering scheme) in the oligomerization interface of FraC, equinatoxin II (EqtII), and sticholysin II (StII) impairs the pore formation activity of these proteins. Our results allow for the extension of the importance of FraC protein-protein interactions in the stabilization of the oligomeric intermediates of StII and EqtII pointing out that all of these proteins follow a similar pathway of membrane disruption. These findings support the hybrid pore proposal as the universal model of actinoporins pore formation.Abbreviations: AA, acrylamide; CAS, computational alanine scanning; CD, circular dichroism; CF, carboxyfluorescein; EM, energy minimization; EqtII, equinatoxin II; FraC, fragaceatoxin C; DG bind , binding free energy; DG polar , polar desolvation energy; DG nonpolar , nonpolar desolvation energy; DG solvat , solvation free energy; HA, hemolytic activity; Ksv, SternVolmer constant; m, slope of regression fit/line; MD, molecular dynamic; MLV, multilamellar vesicles; PFP, pore-forming protein; PFT, pore-forming toxins; POPC, 1-palmitoyl-2-oleylphosphatidylcholine; SM, sphingomyelin; StII, sticholysin II; SUV, small unilamellar vesicles; DV ele , electrostatic energy; DV vdw , van der Waals Energy; p, surface pressure; p 0 , initial surface pressure; Dp, increment in surface pressure. Moreover, we reinforce the relevance of dimer formation, which appears to be a functional intermediate in the assembly pathway of some different pore-forming proteins.

show abstract

Effect of sphingomyelin and cholesterol on the interaction of St II with lipidic interfaces

Cited by 59 publications

References 38 publications

Biophysical and biochemical strategies to understand membrane binding and pore formation by sticholysins, pore-forming proteins from a sea anemone

Biophysical and biochemical strategies to understand membrane binding and pore formation by sticholysins, pore-forming proteins from a sea anemone

Photobleaching Reveals Heterogeneous Stoichiometry for Equinatoxin II Oligomers

Disrupting a key hydrophobic pair in the oligomerization interface of the actinoporins impairs their pore‐forming activity

Contact Info

Product

Resources

About