Pericardin, aDrosophilatype IV collagen-like protein is involved in the morphogenesis and maintenance of the heart epithelium during dorsal ectoderm closure

The steps that lead to the formation of a single primitive heart tube are highly conserved in vertebrate and invertebrate embryos. Concerted migration of the two lateral cardiogenic regions of the mesoderm and endoderm (or ectoderm in invertebrates) is required for their fusion at the midline of the embryo. Morphogenetic signals are involved in this process and the extracellular matrix has been proposed to serve as a link between the two layers of cells.Pericardin (Prc), a novel Drosophila extracellular matrix protein is a good candidate to participate in heart tube formation. The protein has the hallmarks of a type IV collagen α-chain and is mainly expressed in the pericardial cells at the onset of dorsal closure. As dorsal closure progresses, Pericardin expression becomes concentrated at the basal surface of the cardioblasts and around the pericardial cells, in close proximity to the dorsal ectoderm. Pericardin is absent from the lumen of the dorsal vessel.Genetic evidence suggests that Prc promotes the proper migration and alignment of heart cells. Df(3)vin6 embryos, as well as embryos in which prc has been silenced via RNAi, exhibit similar and significant defects in the formation of the heart epithelium. In these embryos, the heart epithelium appears disorganized during its migration to the dorsal midline. By the end of embryonic development, cardial and pericardial cells are misaligned such that small clusters of both cell types appear in the heart; these clusters of cells are associated with holes in the walls of the heart. A prc transgene can partially rescue each of these phenotypes, suggesting that prc regulates these events. Our results support, for the first time, the function of a collagen-like protein in the coordinated migration of dorsal ectoderm and heart cells.

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Role of the extracellular matrix protein thrombospondin in the early development of the mouse embryo.

The Journal of Cell Biology ◽

10.1083/jcb.111.6.2713 ◽

1990 ◽

Vol 111 (6) ◽

pp. 2713-2723 ◽

Cited By ~ 39

Author(s):

K S O'Shea ◽

L H Liu ◽

L H Kinnunen ◽

V M Dixit

Keyword(s):

Extracellular Matrix ◽

Matrix Protein ◽

Inner Cell Mass ◽

Cell Mass ◽

Cell Types ◽

Extracellular Matrix Protein ◽

Heparin Binding ◽

Cell Stage ◽

Binding Domains ◽

Heparin Binding Domain

The distribution of the extracellular matrix protein thrombospondin (TSP) in cleavage to egg cylinder staged mouse embryos and its role in trophoblast outgrowth from cultured blastocysts were examined. TSP was present within the cytoplasm of unfertilized eggs; in fertilized one- to four-cell embryos; by the eight-cell stage, TSP was also densely deposited at cell-cell borders. In the blastocyst, although TSP was present in all three cell types; trophectoderm, endoderm, and inner cell mass (ICM), it was enriched in the ICM and at the surface of trophectoderm cells. Hatched blastocysts grown on matrix-coated coverslips formed extensive trophoblast outgrowths on TSP, grew slightly less avidly on laminin, or on a 140-kD fragment of TSP containing its COOH terminus and putative cell binding domains. There was little outgrowth on the NH2 terminus heparin-binding domain. Addition of anti-TSP antibodies (but not GRGDS) to blastocysts growing on TSP strikingly inhibited outgrowth. Consistent with its early appearance and presence in trophoblast cells during implantation, TSP may play an important role in the early events involved in mammalian embryogenesis.

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The major laminin receptor of mouse embryonic stem cells is a novel isoform of the alpha 6 beta 1 integrin.

The Journal of Cell Biology ◽

10.1083/jcb.115.3.843 ◽

1991 ◽

Vol 115 (3) ◽

pp. 843-850 ◽

Cited By ~ 105

Author(s):

H M Cooper ◽

R N Tamura ◽

V Quaranta

Keyword(s):

Extracellular Matrix ◽

Matrix Protein ◽

Es Cells ◽

Embryonic Stem ◽

Cell Types ◽

Cytoplasmic Domain ◽

Laminin Receptor ◽

Extracellular Matrix Protein ◽

Cytoplasmic Domains ◽

Alternative Mrna Splicing

Laminin is the first extracellular matrix protein expressed in the developing mouse embryo. It is known to influence morphogenesis and affect cell migration and polarization. Several laminin receptors are included in the integrin family of extracellular matrix receptors. Ligand binding by integrin heterodimers results in signal transduction events controlling cell motility. We report that the major laminin receptor on murine embryonic stem (ES) cells is the integrin heterodimer alpha 6 beta 1, an important receptor for laminin in neurons, lymphocytes, macrophages, fibroblasts, platelets and other cell types. However, the cytoplasmic domain of the ES cell alpha 6 (alpha 6 B) differs totally from the reported cytoplasmic domain amino acid sequence of alpha 6 (alpha 6 A). Comparisons of alpha 6 cDNAs from ES cells and other cells suggest that the alpha 6 A and alpha 6 B cytoplasmic domains derive from alternative mRNA splicing. Anti-peptide antibodies to alpha 6 A are unreactive with ES cells, but react with mouse melanoma cells and embryonic fibroblasts. When ES cells are cultured under conditions that permit their differentiation, they become positive for alpha 6 A, concurrent with the morphologic appearance of differentiated cell types. Thus, expression of the alpha 6 B beta 1 laminin receptor may be favored in undifferentiated, totipotent cells, while the expression of alpha 6 A beta 1 receptor occurs in committed lineages. While the functions of integrin alpha chain cytoplasmic domains are not understood, it is possible that they contribute to transferring signals to the cell interior, e.g., by delivering cytoskeleton organizing signals in response to integrin engagement with extracellular matrix ligands. It is therefore reasonable to propose that the cellular responses to laminin may vary, according to what alpha subunit isoform (alpha 6 A or alpha 6 B) is expressed as part of the alpha 6 beta 1 laminin receptor. The switch from alpha 6 B to alpha 6 A, if confirmed in early embryos, could then be of striking potential relevance to the developmental role of laminin.

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1280: Increased Susceptibility to Genitovaginal Prolapse Associated with a Polymorphism in the Promoter of the Extracellular Matrix Protein LAMC1

The Journal of Urology ◽

10.1016/s0022-5347(18)31494-0 ◽

2007 ◽

Vol 177 (4S) ◽

pp. 421-422

Author(s):

Ganka Nikolova ◽

Christian O. Twiss ◽

Hane Lee ◽

Nelson Stanley ◽

Janet Sinsheimer ◽

...

Keyword(s):

Extracellular Matrix ◽

Matrix Protein ◽

Extracellular Matrix Protein ◽

Increased Susceptibility

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Homogenous overexpression of the extracellular matrix protein Netrin-1 in a hollow fiber bioreactor

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11438-0 ◽

2021 ◽

Author(s):

Aniel Moya-Torres ◽

Monika Gupta ◽

Fabian Heide ◽

Natalie Krahn ◽

Scott Legare ◽

...

Keyword(s):

Extracellular Matrix ◽

Hollow Fiber ◽

Mammalian Cells ◽

Matrix Protein ◽

Continuous Production ◽

Extracellular Matrix Protein ◽

Close Monitoring ◽

High Quality ◽

Biolayer Interferometry ◽

Hollow Fiber Bioreactor

Abstract The production of recombinant proteins for functional and biophysical studies, especially in the field of structural determination, still represents a challenge as high quality and quantities are needed to adequately perform experiments. This is in part solved by optimizing protein constructs and expression conditions to maximize the yields in regular flask expression systems. Still, work flow and effort can be substantial with no guarantee to obtain improvements. This study presents a combination of workflows that can be used to dramatically increase protein production and improve processing results, specifically for the extracellular matrix protein Netrin-1. This proteoglycan is an axon guidance cue which interacts with various receptors to initiate downstream signaling cascades affecting cell differentiation, proliferation, metabolism, and survival. We were able to produce large glycoprotein quantities in mammalian cells, which were engineered for protein overexpression and secretion into the media using the controlled environment provided by a hollow fiber bioreactor. Close monitoring of the internal bioreactor conditions allowed for stable production over an extended period of time. In addition to this, Netrin-1 concentrations were monitored in expression media through biolayer interferometry which allowed us to increase Netrin-1 media concentrations tenfold over our current flask systems while preserving excellent protein quality and in solution behavior. Our particular combination of genetic engineering, cell culture system, protein purification, and biophysical characterization permitted us to establish an efficient and continuous production of high-quality protein suitable for structural biology studies that can be translated to various biological systems. Key points • Hollow fiber bioreactor produces substantial yields of homogenous Netrin-1 • Biolayer interferometry allows target protein quantitation in expression media • High production yields in the bioreactor do not impair Netrin-1 proteoglycan quality Graphical abstract

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