Fibrillins, Fibulins, and Matrix-Associated Glycoprotein Modulate the Kinetics and Morphology of <i>in Vitro</i> Self-Assembly of a Recombinant Elastin-like Polypeptide

Cirulis, Judith T.; Bellingham, Catherine M.; Davis, Elaine C.; Hubmacher, Dirk; Reinhardt, Dieter P.; Mecham, Robert P.; Keeley, Fred W.

doi:10.1021/bi8005384

Cited by 75 publications

(121 citation statements)

References 52 publications

Supporting

Mentioning

107

Contrasting

Order By: Relevance

“…4, C and D). Such clumping behavior of colloidal droplets has previously been reported by us (56), and it is particularly characteristic of elastin-like polypeptides with increased tendencies for ␤-sheet formation (30).…”

Section: Mutant Elastin-like Polypeptides Have Multiple Possiblesupporting

confidence: 78%

“…We and others have previously shown that colloidal droplets in suspensions held above the coacervation temperature undergo a maturation process involving growth by coalescence and/or clustering (21,29,56,57). We therefore used light microscopy to compare maturation morphologies of the coacervate droplets formed by these three polypeptides.…”

Section: Mutant Elastin-like Polypeptides Have Multiple Possiblementioning

confidence: 99%

See 1 more Smart Citation

Conformational Transitions of the Cross-linking Domains of Elastin during Self-assembly

Reichheld

Muiznieks

Stahl

et al. 2014

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

Background: Elastin is a polymeric protein providing extensibility and elastic recoil to tissues. Results: Cross-linking domain structure shifts from random coil to ␤-strand to ␣-helix during assembly of elastin matrix. Conclusion: Cross-linking domains have a previously unappreciated structural lability during assembly, which is highly susceptible to mutations of lysine residues. Significance: Identification of conformational transitions in cross-linking domains of elastin during self-assembly is essential for understanding the mechanisms of formation of the elastic matrix.

show abstract

Section: Mutant Elastin-like Polypeptides Have Multiple Possiblesupporting

confidence: 78%

Section: Mutant Elastin-like Polypeptides Have Multiple Possiblementioning

confidence: 99%

Conformational Transitions of the Cross-linking Domains of Elastin during Self-assembly

Reichheld

Muiznieks

Stahl

et al. 2014

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…Although both of these polypeptides exhibited the presence of ␤-structure as dried monomers as well as in the aggregated state, given the disruptive nature of prolines against ␤-sheet formation, it is probable that domain P6N permits a more extended ␤-structure motif than domain P12. Moreover, the introduction of greater spacing between proline residues correlated with the progressive retardation of droplet growth, consistent with more rapid loss of surface fluidity and stabilization of droplet surfaces, preventing coalescence (30,34). Growing evidence shows that water-hydrophobic interfaces promote the self-organization of amphipathic sequences into ␤-sheet structures (53)(54)(55).…”

Section: Proline Prevents the Aggregation Of Exposed Hydrophobicmentioning

confidence: 73%

“…Droplets typically grow (mature) by coalescence before attaining a stable final diameter. The stabilized droplet size is highly dependent on the protein sequence and concentration and on the solvent environment, including the presence of other extracellular matrix proteins (30,34). In this study, the effect of proline spacing on the growth and aggregation characteristics of coacervate droplets was monitored in real time by light microscopy.…”

Section: Distribution Of Proline Residues In Hydrophobic Sequencesmentioning

confidence: 99%

Proline Periodicity Modulates the Self-assembly Properties of Elastin-like Polypeptides

Muiznieks

Keeley

2010

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

Elastin is a self-assembling protein of the extracellular matrix that provides tissues with elastic extensibility and recoil. The monomeric precursor, tropoelastin, is highly hydrophobic yet remains substantially disordered and flexible in solution, due in large part to a high combined threshold of proline and glycine residues within hydrophobic sequences. In fact, proline-poor elastin-like sequences are known to form amyloidlike fibrils, rich in ␤-structure, from solution. On this basis, it is clear that hydrophobic elastin sequences are in general optimized to avoid an amyloid fate. However, a small number of hydrophobic domains near the C terminus of tropoelastin are substantially depleted of proline residues. Here we investigated the specific contribution of proline number and spacing to the structure and self-assembly propensities of elastin-like polypeptides. Increasing the spacing between proline residues significantly decreased the ability of polypeptides to reversibly self-associate. Real-time imaging of the assembly process revealed the presence of smaller colloidal droplets that displayed enhanced propensity to cluster into dense networks. Structural characterization showed that these aggregates were enriched in ␤-structure but unable to bind thioflavin-T. These data strongly support a model where proline-poor regions of the elastin monomer provide a unique contribution to assembly and suggest a role for localized ␤-sheet in mediating self-assembly interactions.Elastin is the extracellular matrix protein responsible for the elasticity of vertebrate arterial vessels, connective tissues, lung, and skin. Elastin resilience is afforded by the formation of insoluble fibers, the first step of which involves the selfalignment of elastin monomers, tropoelastin, in a temperature-induced transition known as coacervation, through the association of hydrophobic domains (1, 2). Although highly (Ͼ75%) non-polar in character, tropoelastin remains predominantly monomeric and structurally disordered in solution (3-5) and critically, retains substantial backbone hydration and flexibility even when assembled (6) and cross-linked into mature, polymeric elastic arrays (7-13).Maintenance of structural heterogeneity and dynamics of the elastin backbone is achieved in large part by a high proportional composition of both proline (14%) and glycine (35%) residues within hydrophobic sequences (6, 14). These residues are commonly arranged into repeated motifs based on recurring sequence elements such as PGV and GVA. This includes a seven-fold tandem PGVGVA repeat in domain 24 of the native human elastin sequence (15). Contrary to enhancing coacervation or elastomeric properties, the multiple substitution of glycine residues for prolines within tandem repeat sequences (e.g. PGVGVA to GGVGVA) results in the formation of amyloid-like fibrils, rich in ␤-structure, from solution (6, 14). These structures are conformationally more restricted than native elastomeric sequences as a result of the tighter packing of residues into extended...

show abstract

“…Initially, it was proposed that the RGD motif in fibulin-5 played a role in the final step of elastic fiber assembly by tethering polymerized elastin to surrounding cells (14,28). Subsequent biochemical studies, however, showed that fibulin-5 preferentially binds to the monomeric form of elastin and positively regulates coacervation, but negatively regulates maturation of coacervated elastin in vitro (18,36). Our present study provides genetic evidence that RGDdependent integrins are not directly involved in fibulin-5-mediated elastic fiber assembly in vivo.…”

Section: Discussionmentioning

confidence: 99%

Extracellular matrix proteases contribute to progression of pelvic organ prolapse in mice and humans

Budatha¹,

Roshanravan²,

Zheng³

et al. 2011

J. Clin. Invest.

Self Cite

129

132

View full text Add to dashboard Cite

Pelvic organ prolapse (POP) is a common condition affecting almost half of women over the age of 50. The molecular and cellular mechanisms underlying this condition, however, remain poorly understood. Here we have reported that fibulin-5, an integrin-binding matricellular protein that is essential for elastic fiber assembly, regulated the activity of MMP-9 to maintain integrity of the vaginal wall and prevented development of POP. In murine vaginal stromal cells, fibulin-5 inhibited the β 1 integrin-dependent, fibronectin-mediated upregulation of MMP-9. Mice in which the integrin-binding motif was mutated to an integrin-disrupting motif (Fbln5 RGE/RGE ) exhibited upregulation of MMP-9 in vaginal tissues. In contrast to fibulin-5 knockouts (Fbln5 -/-), Fbln5 RGE/RGE mice were able to form intact elastic fibers and did not exhibit POP. However, treatment of mice with β-aminopropionitrile (BAPN), an inhibitor of matrix cross-linking enzymes, induced subclinical POP. Conversely, deletion of Mmp9 in Fbln5 -/-mice significantly attenuated POP by increasing elastic fiber density and improving collagen fibrils. Vaginal tissue samples from pre-and postmenopausal women with POP also displayed significantly increased levels of MMP-9. These results suggest that POP is an acquired disorder of extracellular matrix and that therapies targeting matrix proteases may be successful for preventing or ameliorating POP in women. IntroductionPelvic organ prolapse (POP) is characterized by abnormal protrusion of female pelvic organs involving the uterus, bladder, and vagina (reviewed in refs. 1-3). Epidemiologic studies indicate that (a) vaginal birth, aging, and increased body mass index are major risk factors for the development of POP and (b) more than 1 pathology may be involved to exhibit full anatomical loss of support. Although approximately 11% of women have surgery for POP or urinary incontinence in their lifetimes (4), to date, effective therapies to prevent progression of POP have not been established, thereby imposing profound social and financial burden to affected individuals (3).Despite a difference in anatomical position of pelvic organs relative to the body axis and pelvic floor, rodent models of POP have provided important tools to study underlying mechanisms of prolapse. In contrast to an observation that rectal prolapse is frequently associated with the presence of chronic inflammatory bowel disease (5), POP has been found in animals with defective ECM proteins, including fibulin-3, fibulin-5, and lysyl oxidaselike-1 (LOXL-1) (an enzyme that predominantly catalyzes crosslinking of elastin) (6-8). Interestingly, these proteins are abundantly expressed in the vaginal wall and involved in synthesis and assembly of elastic fibers. It is also known that uterosacral ligaments support the vaginal wall and that Hoxa11 is essential for formation of uterosacral ligaments in mice (9). Hoxa11-deficient mice exhibit increased mobility of the uterus; however,

show abstract

Fibrillins, Fibulins, and Matrix-Associated Glycoprotein Modulate the Kinetics and Morphology of in Vitro Self-Assembly of a Recombinant Elastin-like Polypeptide

Cited by 75 publications

References 52 publications

Conformational Transitions of the Cross-linking Domains of Elastin during Self-assembly

Conformational Transitions of the Cross-linking Domains of Elastin during Self-assembly

Proline Periodicity Modulates the Self-assembly Properties of Elastin-like Polypeptides

Extracellular matrix proteases contribute to progression of pelvic organ prolapse in mice and humans

Contact Info

Product

Resources

About