Search results for "Collagen"

Hypusinated eIF5A is required for the translation of collagen.

2021

ABSTRACT Translation of mRNAs that encode peptide sequences with consecutive prolines (polyproline) requires the conserved and essential elongation factor eIF5A to facilitate the formation of peptide bonds. It has been shown that, upon eIF5A depletion, yeast ribosomes stall in polyproline motifs, but also in tripeptide sequences that combine proline with glycine and charged amino acids. Mammalian collagens are enriched in putative eIF5A-dependent Pro-Gly-containing tripeptides. Here, we show that depletion of active eIF5A in mouse fibroblasts reduced collagen type I α1 chain (Col1a1) content, which concentrated around the nuclei. Moreover, it provoked the upregulation of endoplasmic reticul…

Collagen overglycosylation: a biochemical feature that may contribute to bone quality.

2005

Skeletal ability to resist mechanical stress is determined by bone amount and quality, which relies on macro- and micro-architecture, turnover, bone matrix, and mineralisation; the role of collagen has not been clearly elucidated. Numerous post-translational steps are involved in collagen type I biosynthesis, including residue hydroxylation and glycosylation catalysed by enzymes that work until the protein folds forming the triple helix; therefore, folding rate regulates these processes. Overglycosylated hydroxylysines are poor substrates for epsilon-amino group deamination which initiates cross-link formation. Three clinical conditions associated with fractures may relate collagen overglyc…

072 Collagen gene expression and tenascin pattern in normal, osteoarthritic, and rheumatoid connective tissues

1992

The extracellular matrix consists of four major components, namely collagens, elastin, proteoglyeans and glycoproteins. Collagens are important members of the ECM, forming a family of at least t 3 different structurally related proteins. Tenascin, synonymous with cytoactin, hexabrachion and J1, is a new member of matrix glycoproteins with a molecular mass of 1200 kD. It exhibits a "hexabrachion" structure with an ellipsoid central globule from which six arms of 75 nm in length diverge in a T-junction arrangement [1]. Rheumatoid arthritis (RA) belongs to the group of connective tissue diseases. In contrast to abundant data about ECM-changes in systemic sclerodermia [2] the matrix alterations…

Identification of Type I and IX Collagens in the Ascidian Ciona intestinalis

2001

Immunohistochemical methods showed that a type I collagen is a component of the tunic of Ciona intestinalis, involved in the encapsulation process. Since the fibril-forming collagen types are characterized by triple helical domain with a highly preserved Gly-Xaa-Yaa repeated sequence, a probe coding the fibril-forming type I collagen of the echinoderm Paracentrotus lividus was used to identify ascidian cDNA clones. Northern blot hybridization established that P. lividus probe cross-hybridizes with a 6 Kb C. intestinalis mRNA isolated from the pharynx. Using the echinodermal type I collagen cDNA as a probe several positive clones were identified. Analysis of sequence and the deduced amino ac…

Changes in collagen cross-linking of articular cartilage are revealed by spectral reflectance imaging

2012

Excessive cross-linking of collagen during aging may contribute to degeneration of articular cartilage. Traditionally, the amount of cross-links is derived by using destructive high-performance liquid chromatography (HPLC). However, a sensitive, non-destructive method could help to evaluate tissue integrity, including cross-links. We increased collagen cross-linking in bovine articular cartilage by controlled threose incubation. During the incubation, optical spectral reflectance images of the samples were captured and related to HPLC results using regression analysis. Significant correlations with reflectance and cross-links were observed. When further developed the optical method may enab…

In-vitro Proteoglykansynthese in redifferenzierten Chondrozyten

1989

Human chondrocytes growing in monolayer cultures de-differentiate and produce type I collagen. They re-differentiate and resume their in-vivo characteristics (including the production of type II collagen) when cultured in an agarose-gel. To characterize the modulated cells in more detail, biochemical studies were performed in chondrocytes suspended in agarose for 1 to 3 weeks.

Inserto di collagene biodegradabile vs mitomicina-C nella trabeculectomia: risultati a medio termine di uno studio prospettico di fase II.

2010

IDENTIFICATION OF TYPE V COLLAGEN-BINDING PROTEINS IN 8701-BC BREAST CANCER CELLS

2012

Minireview: Aspects of collagen changes in breast cancer

2013

Collagen changes in the extracellular matrix of tumor-affected human breast: a tale of OF/LB and type V collagens

2010

It is widely acknowledged that the extracellular matrix (ECM) ofconnective tissues plays active roles in numerous biological processessuch as cell differentiation, life/death promotion and carcinogenesis.Ductal infiltrating carcinoma (DIC) of the breast is a highly metastatictumor histotype commonly associated with drastic massive alterations ofECM architecture and composition, especially concerning its collagenouscomponent. In particular, it was demonstrated that the stroma of DIC ofthe human breast contains a considerable amount of an embryo-foetalcollagen type (OF/LB), while type V collagen, which is a minorcomponent of normal human breast ECM, undergoes over-deposition inthe affected gl…