Modeling Curvature-Dependent Subcellular Localization of the Small Sporulation Protein SpoVM in Bacillus subtilis

Wasnik, Vaibhav; Wingreen, Ned S.; Mukhopadhyay, Ranjan

doi:10.1371/journal.pone.0111971

Cited by 17 publications

(9 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the current investigation, we eliminated limitations associated with giant unilamellar vesicles (variability in vesicle size and associated variability in membrane stiffness) by using SSLBs, in which a single phospholipid bilayer is assembled on the surface of silica beads of defined size (29,30). In addition to providing a more strictly defined membrane radius of curvature (determined by the diameter of the silica bead), the use of a supported bilayer system eliminates osmotic-dependent variability in membrane tension across vesicle curvatures (31).…”

Section: Resultsmentioning

confidence: 99%

Structural basis for the geometry-driven localization of a small protein

Gill

Castaing

Hsin

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

In bacteria, certain shape-sensing proteins localize to differently curved membranes. During sporulation in Bacillus subtilis, the only convex (positively curved) surface in the cell is the forespore, an approximately spherical internal organelle. Previously, we demonstrated that SpoVM localizes to the forespore by preferentially adsorbing onto slightly convex membranes. Here, we used NMR and molecular dynamics simulations of SpoVM and a localization mutant (SpoVM P9A ) to reveal that SpoVM's atypical amphipathic α-helix inserts deeply into the membrane and interacts extensively with acyl chains to sense packing differences in differently curved membranes. Based on binding to spherical supported lipid bilayers and Monte Carlo simulations, we hypothesize that SpoVM's membrane insertion, along with potential cooperative interactions with other SpoVM molecules in the lipid bilayer, drives its preferential localization onto slightly convex membranes. Such a mechanism, which is distinct from that used by high curvature-sensing proteins, may be widely conserved for the localization of proteins onto the surface of cellular organelles.ArfGAP1 | SpoIVA | DivIVA | curvature sensing | lipid packing

show abstract

Section: Resultsmentioning

confidence: 99%

Structural basis for the geometry-driven localization of a small protein

Gill

Castaing

Hsin

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…7b) 48 . SpoVM is structurally an amphipathic helix and, like other amphipathic helices such as the ALPS-motif containing proteins 44 , has a preference for positively curved membranes due to reduced lipid packing density in the outer leaflet that facilitates accommodation of a bulky alpha-helix 49 (Fig. 7c).…”

Section: Discussionmentioning

confidence: 99%

Transmembrane protein sorting driven by membrane curvature

et al. 2015

View full text Add to dashboard Cite

The intricate structure of prokaryotic and eukaryotic cells depends on the ability to target proteins to specific cellular locations. In most cases, we have a poor understanding of the underlying mechanisms. A typical example is the assembly of bacterial chemoreceptors at cell poles. Here we show that the classical chemoreceptor TlpA of Bacillus subtilis does not localize according to the consensus stochastic nucleation mechanism but accumulates at strongly curved membrane areas generated during cell division. This preference was confirmed by accumulation at non-septal curved membranes. Localization appears to be an intrinsic property of the protein complex and does not rely on chemoreceptor clustering, as was previously shown for Escherichia coli. By constructing specific amino-acid substitutions, we demonstrate that the preference for strongly curved membranes arises from the curved shape of chemoreceptor trimer of dimers. These findings demonstrate that the intrinsic shape of transmembrane proteins can determine their cellular localization.

show abstract

“…Finally, the last term takes long-range repulsion into account in an effective way, by growing faster than the cluster size k . In the extreme case where each protein pair inside the cluster experiences the same repulsive energy ϵrep, the total repulsive energy is ϵrep0.166667emk2/2, thus α=2 [157]; χ0 measures the intensity of the repulsion. This expression is the so-called “droplet approximation” with an additional non-extensive term (i.e., a term growing faster than k ).…”

Section: In Thermodynamic Equilibriummentioning

confidence: 99%

A Rationale for Mesoscopic Domain Formation in Biomembranes

2018

View full text Add to dashboard Cite

Cell plasma membranes display a dramatically rich structural complexity characterized by functional sub-wavelength domains with specific lipid and protein composition. Under favorable experimental conditions, patterned morphologies can also be observed in vitro on model systems such as supported membranes or lipid vesicles. Lipid mixtures separating in liquid-ordered and liquid-disordered phases below a demixing temperature play a pivotal role in this context. Protein-protein and protein-lipid interactions also contribute to membrane shaping by promoting small domains or clusters. Such phase separations displaying characteristic length-scales falling in-between the nanoscopic, molecular scale on the one hand and the macroscopic scale on the other hand, are named mesophases in soft condensed matter physics. In this review, we propose a classification of the diverse mechanisms leading to mesophase separation in biomembranes. We distinguish between mechanisms relying upon equilibrium thermodynamics and those involving out-of-equilibrium mechanisms, notably active membrane recycling. In equilibrium, we especially focus on the many mechanisms that dwell on an up-down symmetry breaking between the upper and lower bilayer leaflets. Symmetry breaking is an ubiquitous mechanism in condensed matter physics at the heart of several important phenomena. In the present case, it can be either spontaneous (domain buckling) or explicit, i.e., due to an external cause (global or local vesicle bending properties). Whenever possible, theoretical predictions and simulation results are confronted to experiments on model systems or living cells, which enables us to identify the most realistic mechanisms from a biological perspective.

show abstract

Modeling Curvature-Dependent Subcellular Localization of the Small Sporulation Protein SpoVM in Bacillus subtilis

Cited by 17 publications

References 34 publications

Structural basis for the geometry-driven localization of a small protein

Structural basis for the geometry-driven localization of a small protein

Transmembrane protein sorting driven by membrane curvature

A Rationale for Mesoscopic Domain Formation in Biomembranes

Contact Info

Product

Resources

About