Conformations of Primary Amphipathic Carrier Peptides in Membrane Mimicking Environments

Chaloin, Laurent; Vidal, Pierre; Heitz, Annie; Mau, N. Van; Méry, Jean; Divita, Gilles; Heitz, Fréderic

doi:10.1021/bi9708491

Cited by 86 publications

(61 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…MP51 or MP51P was initially diluted to a final concentration of 0.1 mg ml Ϫ1 in water or phosphate buffer (pH 7.0), and structural variations were measured as a function of changes in the initial CD spectrum upon addition of increasing concentrations of methanol or 2,2,2-trifluoroethanol (TFE). CD spectra were measured between 185 and 260 nm, and ellipticity values were calculated at 220 nm as described previously (32 (35) and HSQC-TOCSY spectra were recorded at natural abundance for carbon identification. The carrier frequency was centered on the water signal, and the solvent was suppressed by continuous low power irradiation during the relaxation delay and during the mixing time for NOESY spectra.…”

Section: Methodsmentioning

confidence: 99%

An Essential Phosphorylation-site Domain of Human cdc25C Interacts with Both 14-3-3 and Cyclins

Morris¹,

Heitz²,

Méry³

et al. 2000

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

Human cdc25C is a dual-specificity phosphatase involved in the regulation of cell cycle progression in both unperturbed cells and in cells subject to DNA damage or replication checkpoints. In this study, we describe the structure-function relationship of an essential domain of human cdc25C that interacts with 14-3-3 proteins. We show that this domain is a bi-functional interactive motif that interacts with cyclins primarily through their P-box motif in addition to 14-3-3 proteins. Characterization of the structural features of this domain by NMR and circular dichroism reveals two distinct ␣ helical moieties interconnected by a loop carrying the 14-3-3 binding site. Moreover, the helical folding is induced upon binding to 14-3-3, suggestive of a conformational regulation of this domain of cdc25C through interactions with partner proteins in vivo. Combining our structural and biochemical data, we propose a detailed model of the molecular mechanism of cdc25C regulation by differential association with 14-3-3 and cdc2-cyclin B.Cdc25 protein phosphatases play important roles in the control of cell cycle progression in eukaryotes by activation of cyclin-dependent kinases (cdks) 1 through dephosphorylation of two conserved residues, Thr 14 and Tyr 15 (1, 2). In addition to their essential function in the normal cell cycle, cdc25 phosphatases are involved in the checkpoint-induced control of cell cycle progression (3-5). Finally, cdc25 phosphatases have been shown to possess an important oncogenic potential and to be overexpressed in a variety of cancers and cancer cell lines (6, 7). In humans three cdc25 isoforms exhibiting different structural and functional characteristics have been identified. Whereas cdc25A is involved in activation of cyclin-dependent kinases at the G 1 /S transition (8 -10), cdc25B and cdc25C both play important roles in activation of the G 2 /M transition (6,8,(11)(12)(13)(14)(15). The mitotic isoform cdc25C is regulated throughout the cell cycle by differential phosphorylation (15)(16)(17)(18)(19) (3-5, 20 -23). Phosphorylation of human cdc25C on Ser 216 creates a consensus 14-3-3 binding site RSXpSXP (X being any amino acid; pS corresponding to phospho-Ser 216 ) (24 -25), which represents an important regulatory motif affecting the fate of cdc25C both during a normal cell cycle and in the DNA damage and replication checkpoints (3-5, 18, 19). Recent studies in fission yeast, Xenopus, and mammalian cells reveal that this phosphorylation promotes binding of 14-3-3 proteins to cdc25 phosphatases in vivo, thus preventing their nuclear accumulation as well as their mitotic function (3-5, 26 -30). In fission yeast, the 14-3-3 homolog Rad24 regulates the untimely nuclear localization of cdc25 by enhancing the nuclear export of cdc25 thanks to its nuclear export signal (26). In Xenopus and in human cells, in contrast, 14-3-3 proteins seem to promote the increased cytoplasmic retention of cdc25 by preventing recognition of the bipartite nuclear localization sequence (NLS) of cdc25 by the nuclear import...

show abstract

Section: Methodsmentioning

confidence: 99%

An Essential Phosphorylation-site Domain of Human cdc25C Interacts with Both 14-3-3 and Cyclins

Morris¹,

Heitz²,

Méry³

et al. 2000

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…A number of other cell-penetrating peptides that derive not from natural proteins but from the engineering of various short peptides have been described, such as, for example, transportan, 10,20 the model amphipathic peptide (MAP), 16,17 and various signal sequence-based peptides, 11,12 and homoarginine vectors 34 (see Tables 1 and 2). Transportan is a 27-amino-acid chimeric peptide composed of the neuropeptide galanin and mastoparan-X linked by a central lysine.…”

Section: Other Cell-penetrating Peptidesmentioning

confidence: 99%

“…10 Likewise, it has been reported that MAP and some of the other sequence-based peptides seemingly enter into cells via a nonendocytotic pathway. 11,12,16 The sequence-based peptides resulted from the fusion of a hydrophobic peptide (eg, a signal sequence, a fusion peptide) with the NLS motif, whereas the MAP peptide is a complete canonical amphipathic helix. As observed with pAntp [43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58] , the unconventional internalization of these peptides seems to be neither saturable nor dependent on the cell type 8,10 and could be related to their lipid-binding capacity.…”

Section: Other Cell-penetrating Peptidesmentioning

confidence: 99%

“…As observed with pAntp [43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58] , the unconventional internalization of these peptides seems to be neither saturable nor dependent on the cell type 8,10 and could be related to their lipid-binding capacity. 11,12,17,21 As far as the homoarginine peptides are concerned, they have also been described as entering into cells by an energy-dependent nonendocytic process. 34 …”

Section: Other Cell-penetrating Peptidesmentioning

confidence: 99%

See 1 more Smart Citation

Peptide delivery to the brain via adsorptive-mediated endocytosis: Advances with SynB vectors

Drin¹,

Rousselle²,

Scherrmann

et al. 2002

AAPS J

View full text Add to dashboard Cite

Biological membranes normally restrict the passage of hydrophilic molecules. This impairs the use of a wide variety of drugs for biomedical applications. To overcome this problem, researchers have developed strategies that involve conjugating the molecule of interest to one of a number of peptide entities that are efficiently transported across the cell membranes. In the past decade, a number of different peptide families with the ability to cross the cell membranes have been identified. Certain of these families enter the cells by a receptor-independent mechanism, are short (10-27 amino acid residues), and can deliver successfully various cargoes across the cell membrane into the cytoplasm or nucleus. Surprisingly, some of these vectors, the SynB vectors, have also shown the ability to deliver hydrophilic molecules across the blood-brain barrier, one of the major obstacles to the development of drugs to combat diseases affecting the CNS.The most important factors determining the extent to which a molecule will be delivered from the blood into the CNS are lipid solubility, molecular mass, and charge. Therefore, based simply on lipid solubility and molecular mass, any peptide-based or oligonucleotide-based neuropharmaceutical will almost certainly be impeded by the BBB. To overcome the limited access of drugs to the brain, at least 3 strategies have been developed that achieve BBB penetration 2-5 :1. Neurosurgery-based strategies, which bypass the BBB by means of intraventricular drug infusion, intracerebral infusion, or disruption of the BBB; 2. Pharmacology-based strategies, some examples of which employ lipidation, or chemical modification of the drug to improve its ability to diffuse across the BBB; and KEYWORDS: intracellular delivery, peptide vector, blood-brain barrier, multidrug resistance. 3. Physiology-based strategies, which take advantage of BBB nutrient carriers or specific receptors, mediating transport via these transporter systems. One example has been to conjugate the therapeutic drug with a protein or a monoclonal antibody that gains access to the brain by either receptor -or adsorptive-mediated transcytosis (eg, transferrin receptor-mediated transfer).2

show abstract

“…These cell-penetrating peptides (CPPs) 1 are either basic segments of RNA-or DNA-binding proteins (4,5,6) such as pAntp- (43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55)(56)(57)(58) and Tat-(48 -60) , or artificial peptides such as Transportan (7), model amphipathic peptide (MAP) (8), or other sequence-based constructs (9,10). In addition, the SynB peptides constitute a distinct family of vectors that derive from protegrin 1 (PG-1), an antimicrobial peptide (11).…”

mentioning

confidence: 99%

Studies on the Internalization Mechanism of Cationic Cell-penetrating Peptides

Drin

Cottin

Blanc

et al. 2003

Journal of Biological Chemistry

492

395

View full text Add to dashboard Cite

A great deal of data has been amassed suggesting that cationic peptides are able to translocate into eucaryotic cells in a temperature-independent manner. Although such peptides are widely used to promote the intracellular delivery of bioactive molecules, the mechanism by which this cell-penetrating activity occurs still remains unclear. Here, we present an in vitro study of the cellular uptake of peptides, originally deriving from protegrin (the SynB peptide vectors), that have also been shown to enhance the transport of drugs across the blood-brain barrier. In parallel, we have examined the internalization process of two lipid-interacting peptides, SynB5 and pAntp-(43-58), the latter corresponding to the translocating segment of the Antennapedia homeodomain. We report a quantitative study of the time-and dose-dependence of internalization and demonstrate that these peptides accumulate inside vesicular structures. Furthermore, we have examined the role of endocytotic pathways in this process using a variety of metabolic and endocytosis inhibitors. We show that the internalization of these peptides is a temperatureand energy-dependent process and that endosomal transport is a key component of the mechanism. Altogether, our results suggest that SynB and pAntp-(43-58) peptides penetrate into cells by an adsorptive-mediated endocytosis process rather than temperature-independent translocation.

show abstract

Conformations of Primary Amphipathic Carrier Peptides in Membrane Mimicking Environments

Cited by 86 publications

References 33 publications

An Essential Phosphorylation-site Domain of Human cdc25C Interacts with Both 14-3-3 and Cyclins

An Essential Phosphorylation-site Domain of Human cdc25C Interacts with Both 14-3-3 and Cyclins

Peptide delivery to the brain via adsorptive-mediated endocytosis: Advances with SynB vectors

Studies on the Internalization Mechanism of Cationic Cell-penetrating Peptides

Contact Info

Product

Resources

About