Effect of Detergents on the Association of the Glycophorin A Transmembrane Helix

Fisher, Lillian Estelle; Engelman, Donald M.; Sturgis, James N.

doi:10.1016/s0006-3495(03)74728-6

Cited by 119 publications

(174 citation statements)

References 44 publications

Supporting

Mentioning

162

Contrasting

Order By: Relevance

“…As expected (15), below the cmc we observe a rapid increase in the apparent fraction of dimers due to the formation of higher-order aggregates, above the cmc a more usual sensitivity. It was previously shown that the apparent free energy of interaction is in first approximation related to the logarithm of micellar detergent concentration (15). In the case presented here, the gradient of the sensitivity appears to be ∼7 kJ/mol.…”

Section: Quantitative Assessment Of Transmembrane Domain Interactionssupporting

confidence: 86%

“…Examination of the sensitivity of dimer formation to the detergent concentration in the range of 1 mM [just under the critical micellar concentration (cmc) of the detergent] to 2 mM is shown in Figure 3B. As expected (15), below the cmc we observe a rapid increase in the apparent fraction of dimers due to the formation of higher-order aggregates, above the cmc a more usual sensitivity. It was previously shown that the apparent free energy of interaction is in first approximation related to the logarithm of micellar detergent concentration (15).…”

Section: Quantitative Assessment Of Transmembrane Domain Interactionsmentioning

confidence: 56%

See 1 more Smart Citation

A Dimerization Hierarchy in the Transmembrane Domains of the HER Receptor Family

2007

Self Cite

View full text Add to dashboard Cite

Bitopic membrane proteins offer an opportunity for studying transmembrane domain interactions without the structural complexity inherent to multitopic integral membrane proteins. To date, only homomeric associations have been extensively studied quantitatively. Here we propose to assess the thermodynamics of heteromeric associations, which opens the way to investigating specificity and selectivity. A very interesting system of biological relevance with single transmembrane domains possibly involved in interactions with different partners is the EGFR receptor family. The four members, all tyrosine kinase receptors, are involved in an interaction network that potentially leads to a complete set of homoand heterodimers, ideally suited to such a study. Furthermore, the transmembrane domains of these receptors have been previously implicated in their function in the past by mutations in the transmembrane domain leading to constitutive activation. We demonstrate, using a fluorescence-based measurement of interaction energies, a hierarchy of transmembrane domain interactions ranging from a noninteractive pair to strong dimerization. We propose a structural model based on the crystal structure of the EGFR dimer, to show how the dimeric structure favors these interactions. The correlation we observe between transmembrane domain and whole receptor interaction hierarchies opens a new perspective, suggesting a role for transmembrane receptor domains in the modulation of receptor signaling.

show abstract

Section: Quantitative Assessment Of Transmembrane Domain Interactionssupporting

confidence: 86%

Section: Quantitative Assessment Of Transmembrane Domain Interactionsmentioning

confidence: 56%

A Dimerization Hierarchy in the Transmembrane Domains of the HER Receptor Family

2007

Self Cite

View full text Add to dashboard Cite

show abstract

“…Structures are shown without the long N-terminal loop and helix β for simplicity. denature water-soluble proteins, hydrophobic regions of integral membrane proteins have been shown to display a strong affinity in their native state for complete detergent micelles (48)(49)(50)(51). Indeed, structures of several integral membrane proteins such as the tetrameric KcsA potassium channel (52), the Na,K-ATPase regulatory protein FXYD1 (53), MerF of the bacterial mercury detoxification system (54), and subunit c of ATP synthase (55) have been investigated in SDS by NMR spectroscopy.…”

Section: Discussionmentioning

confidence: 99%

Structural investigation of the C-terminal catalytic fragment of presenilin 1

Sobhanifar

Schneider

Löhr

et al. 2010

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

View full text Add to dashboard Cite

The γ-secretase complex has a decisive role in the development of Alzheimer's disease, in that it cleaves a precursor to create the amyloid β peptide whose aggregates form the senile plaques encountered in the brains of patients. Γ-secretase is a member of the intramembrane-cleaving proteases which process their transmembrane substrates within the bilayer. Many of the mutations encountered in early onset familial Alzheimer's disease are linked to presenilin 1, the catalytic component of γ-secretase, whose active form requires its endoproteolytic cleavage into N-terminal and C-terminal fragments. Although there is general agreement regarding the topology of the N-terminal fragment, studies of the C-terminal fragment have yielded ambiguous and contradictory results that may be difficult to reconcile in the absence of structural information. Here we present the first structure of the C-terminal fragment of human presenilin 1, as obtained from NMR studies in SDS micelles. The structure reveals a topology where the membrane is likely traversed three times in accordance with the more generally accepted nine transmembrane domain model of presenilin 1, but contains unique structural features adapted to accommodate the unusual intramembrane catalysis. These include a putative half-membrane-spanning helix N-terminally harboring the catalytic aspartate, a severely kinked helical structure toward the C terminus as well as a soluble helix in the assumed-to-be unstructured N-terminal loop.cell-free protein expression | gamma secretase | intramembrane proteolysis | membrane protein structure A lzheimer's disease is the most common form of dementia and affects more than 25 million people worldwide. The most characteristic histological feature of Alzheimer's disease is the presence of long, insoluble amyloid fibrils composed of amyloid β (Aβ) peptide which, either alone or as reservoirs for soluble Aβ oligomers (1, 2), appear to be the primary species responsible for the massive neuronal injury presented in patients. Aβ generation is categorized under an unusual physiological phenomenon termed regulated intramembrane proteolysis. Here, the amyloid precursor protein first sheds its ectodomain mediated by β-secretase. The remaining membrane-bound C-terminal fragment is subsequently processed at a γ-cleavage site by the γ-secretase complex, a multisubunit protease whose minimal essential components include presenilin 1 (PS1) or presenilin-2 (PS2), anterior pharynx-defective, nicastrin, and presenilin enhancer 2 (3). The pathological relevance of this final step lies in the observation that γ-cleavage is variable and can occur after three distinct positions, 38, 40, and 42, whose selection influences the self-aggregating potential of the secreted Aβ peptide. Aβ42, although the minor species, appears to show the strongest potency for oligomerization and represents the majority of Aβ in amyloid plaques (4). Over 150 familial Alzheimer's disease associated mutations (www.molgen.ua.ac.be/ADMutations) have been linked to PS1, the catalyt...

show abstract

“…The dry peptides were resolubilized in a 5% SDS detergent solution (45 mM sodium phosphate, uncorrected pH Ϸ7.15, in 2 H 2 O) at a final concentration of 5 mg͞ml (1.7 mM). This procedure promotes GpA dimerization even at very high SDS concentrations (39).…”

Section: Methodsmentioning

confidence: 99%

Amide vibrations are delocalized across the hydrophobic interface of a transmembrane helix dimer

Fang

Senes

Cristian

et al. 2006

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

130

View full text Add to dashboard Cite

The tertiary interactions between amide-I vibrators on the separate helices of transmembrane helix dimers were probed by ultrafast 2D vibrational photon echo spectroscopy. The 2D IR approach proves to be a useful structural method for the study of membrane-bound structures. The 27-residue human erythrocyte protein Glycophorin A transmembrane peptide sequence: KKITLIIFG79VMAGVIGTILLISWG94IKK was labeled at G79 and G94 with 13 tertiary interaction ͉ vibrational spectra ͉ multidimensional spectroscopy T wo-dimensional IR spectroscopy (1-6) is a promising new method with which to probe structures and their motions in complex systems. Recent applications of this method to biologically related molecules have yielded novel structural and dynamical results not readily obtainable by other methods for small peptides (7,8), soluble helices (9, 10), membrane-bound helices (11), lipids (12), ␤-sheets (13, 14), and model secondary structures (15, 16). The 2D IR approach is one that can be immediately applicable to a wide variety of sample types ranging from solutions to solids, including aqueous and lipid environments. The method exposes interactions between spatially nearby vibrational modes by converting three pulse photon echo signals into 2D spectral maps in the IR, analogous to 2D NMR spectra.The amide-I vibrational bands of polypeptides are highly degenerate because, for each residue, their frequencies are approximately the same and the interactions among them are not strong enough to separately display them as individual, assignable transitions. The combination of multiple isotope selection and 2D IR spectroscopy that spreads the transitions into two dimensions proves to be a useful strategy that can simplify and expose the underlying transitions of the diffuse amide bands and allow their features to be characterized at a residue level. For example the 2D IR spectrum of a water-soluble helix selectively substituted with 13 CA 16 O and 13 CA 18 O provided characteristics of pairs of coupled residues and the visualization of the sequence dependence of the structural dynamics (17). This paper introduces a comparable approach to investigate tertiary interactions between vibrational modes in Glycophorin A (GpA), a transmembrane (TM) dimer of interacting helices (Fig. 1). The GpA TM helix provides an excellent prototype for the study of TM helix association, a key event in the folding of membrane proteins (18). The dimer also is an appropriate model for these investigations, because it is stable in a variety of micelles, including SDS (19), and a solution NMR structure is available (20). There are two Gly residues at the dimer interface that allow an intimate contact of the main chain, a feature frequently observed in TM helical interfaces (21,22). Because vibrational coupling is sensitive to distance, the proximity of the backbones is advantageous. GpA also was selected because verification of the applicability of the 2D IR method to membrane protein aggregates is of great interest and because there is a chronic paucity o...

show abstract

Effect of Detergents on the Association of the Glycophorin A Transmembrane Helix

Cited by 119 publications

References 44 publications

A Dimerization Hierarchy in the Transmembrane Domains of the HER Receptor Family

A Dimerization Hierarchy in the Transmembrane Domains of the HER Receptor Family

Structural investigation of the C-terminal catalytic fragment of presenilin 1

Amide vibrations are delocalized across the hydrophobic interface of a transmembrane helix dimer

Contact Info

Product

Resources

About