Proteolysis of fibrillin-2 microfibrils is essential for normal skeletal development

AbstractThe extracellular matrix (ECM) undergoes an orchestrated transition from embryonic to mature ECM that is essential for postnatal life, yet the developmental transition mechanisms for ECM components and macromolecular complexes are poorly defined. Fibrillin microfibrils are macromolecular ECM complexes with important structural and regulatory roles. In mice, Fbn1 and Fbn2 mRNAs, which encode the major microfibrillar components, are strongly expressed during embryogenesis. Fbn2 mRNA levels rapidly decline postnatally, consistent with fibrillin-1 being the major component of adult tissue microfibrils. Here, by combining transgenic and N-terminomics strategies with in vitro analysis of microfibril assembly and intermolecular interactions, we identify cooperative proteolysis of fibrillin-2 by the secreted metalloproteases ADAMTS6 and ADAMTS10 as a mechanism contributing to postnatal fibrillin-1 dominance. The primacy of the protease-substrate relationship between ADAMTS6 and fibrillin-2 was unequivocally established by demonstrating a dramatic reversal of skeletal defects in Adamts6−/− embryos by Fbn2 haploinsufficiency.

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Peritoneal Culture Alters Streptococcus pneumoniae Protein Profiles and Virulence Properties

Infection and Immunity ◽

10.1128/iai.68.10.6082-6086.2000 ◽

2000 ◽

Vol 68 (10) ◽

pp. 6082-6086 ◽

Cited By ~ 15

Author(s):

Carlos J. Orihuela ◽

Rob Janssen ◽

Christopher W. Robb ◽

David A. Watson ◽

David W. Niesel

Keyword(s):

Streptococcus Pneumoniae ◽

Protein Production ◽

Fold Increase ◽

Mrna Levels ◽

Epithelial Cell Lines ◽

Vitro Analysis ◽

Specific Virulence ◽

In Vitro Analysis

ABSTRACT We have examined the properties of Streptococcus pneumoniae cultured in the murine peritoneal cavity and compared its virulence-associated characteristics to those of cultures grown in vitro. Analysis of mRNA levels for specific virulence factors demonstrated a 2.8-fold increase in ply expression and a 2.2-fold increase in capA3 expression during murine peritoneal culture (MPC). Two-dimensional gels and immunoblots using convalescent-phase patient sera and murine sera revealed distinct differences in protein production in vivo (MPC). MPC-grown pneumococci adhered to A549 epithelial cell lines at levels 10-fold greater than those cultured in vitro.

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The native structure of the eukaryotic ribosome

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075890 ◽

1983 ◽

Vol 41 ◽

pp. 432-433

Author(s):

R.A. Milligan ◽

P.N.T. Unwin

Keyword(s):

Ribosomal Proteins ◽

Crystal Form ◽

Native Structure ◽

X Ray Diffraction ◽

Eukaryotic Ribosome ◽

Vitro Analysis ◽

In Vitro Analysis ◽

Resolution Structure ◽

Stable Unit

A detailed understanding of the mechanism of protein synthesis will ultimately depend on knowledge of the native structure of the ribosome. Towards this end we have investigated the low resolution structure of the eukaryotic ribosome embedded in frozen buffer, making use of a system in which the ribosomes crystallize naturally.The ribosomes in the cells of early chicken embryos form crystalline arrays when the embryos are cooled at 4°C. We have developed methods to isolate the stable unit of these arrays, the ribosome tetramer, and have determined conditions for the growth of two-dimensional crystals in vitro, Analysis of the proteins in the crystals by 2-D gel electrophoresis demonstrates the presence of all ribosomal proteins normally found in polysomes. There are in addition, four proteins which may facilitate crystallization. The crystals are built from two oppositely facing P4 layers and the predominant crystal form, accounting for >80% of the crystals, has the tetragonal space group P4212, X-ray diffraction of crystal pellets demonstrates that crystalline order extends to ~ 60Å.

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1163: Radial Dilation of Ureteral Balloons: A Comparative in-Vitro Analysis

The Journal of Urology ◽

10.1016/s0022-5347(18)35308-4 ◽

2005 ◽

Vol 173 (4S) ◽

pp. 315-316

Author(s):

Kari Hendlin ◽

Brynn Lund ◽

Manoj Monga

Keyword(s):

Vitro Analysis ◽

In Vitro Analysis

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An In Vitro Analysis of Ligament Reconstruction or Extension Osteotomy on Trapeziometacarpal Joint Stability and Contact Area

Yearbook of Hand and Upper Limb Surgery ◽

10.1016/s1551-7977(08)70357-1 ◽

2007 ◽

Vol 2007 ◽

pp. 214-215 ◽

Cited By ~ 1

Author(s):

B. Wilhelmi

Keyword(s):

Contact Area ◽

Ligament Reconstruction ◽

Joint Stability ◽

Trapeziometacarpal Joint ◽

Vitro Analysis ◽

In Vitro Analysis

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Role of the 807 C/T Polymorphism of the α2 Gene in Platelet GP Ia Collagen Receptor Expression and Function

Thrombosis and Haemostasis ◽

10.1055/s-0037-1614605 ◽

1999 ◽

Vol 81 (06) ◽

pp. 951-956 ◽

Cited By ~ 59

Author(s):

J. Corral ◽

R. González-Conejero ◽

J. Rivera ◽

F. Ortuño ◽

P. Aparicio ◽

...

Keyword(s):

Venous Thrombosis ◽

Cell Types ◽

Receptor Expression ◽

Case Control Studies ◽

Platelet Surface ◽

Vitro Analysis ◽

And Function ◽

In Vitro Analysis

SummaryThe variability of the platelet GP Ia/IIa density has been associated with the 807 C/T polymorphism (Phe 224) of the GP Ia gene in American Caucasian population. We have investigated the genotype and allelic frequencies of this polymorphism in Spanish Caucasians. The T allele was found in 35% of the 284 blood donors analyzed. We confirmed in 159 healthy subjects a significant association between the 807 C/T polymorphism and the platelet GP Ia density. The T allele correlated with high number of GP Ia molecules on platelet surface. In addition, we observed a similar association of this polymorphism with the expression of this protein in other blood cell types. The platelet responsiveness to collagen was determined by “in vitro” analysis of the platelet activation and aggregation response. We found no significant differences in these functional platelet parameters according to the 807 C/T genotype. Finally, results from 3 case/control studies involving 302 consecutive patients (101 with coronary heart disease, 104 with cerebrovascular disease and 97 with deep venous thrombosis) determined that the 807 C/T polymorphism of the GP Ia gene does not represent a risk factor for arterial or venous thrombosis.

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