| 1. |
- Gustafsson, Renata, et al.
(author)
-
Expression of the novel gene Ened during mouse and Xenopus embryonic development.
- 2008
-
In: International Journal of Developmental Biology. - : UPV/EHU Press. - 1696-3547 .- 0214-6282. ; 52:8, s. 1119-1122
-
Journal article (peer-reviewed)abstract
- We have recently identified 1110032E23Rik as a down-regulated target gene in Fgf receptor-signalling-deficient mouse embryoid bodies. Here, we present the expression pattern of this novel gene, designated Ened (Expressed in Nerve and Epithelium during Development), in mouse and Xenopus laevis embryos. Murine Ened transcripts were first seen at E9.5 in the heart and the gastrointestinal tract. At later stages of gestation, expression could be found in the floor plate, peripheral nervous system, lens epithelium, skin, midline dorsal aorta, lung, kidney and testis. In Xenopus, the expression of the Ened orthologue displayed common RNA distribution in several ectodermal and mesodermal tissues, but also distinct expression in locations including the brain, notochord and blood islands. We suggest that Ened might be a novel target gene of the Fgfr signalling pathway during embryonic development, and that its expression could be modulated by the basement membrane component laminin-111.
|
|
| 2. |
- Gustafsson, Renata
(author)
-
Gene Expression in mESC Deficient in FGFR Signalling and the Identification of the Novel Gene Ened
- 2008
-
Doctoral thesis (other academic/artistic)abstract
- Embryonic stem cells (ESCs) are derived from the inner cell mass (ICM) of blastocyst stage embryos, and upon differentiation into embryoid bodies (EBs) they recapitulate the genetic, cellular and morphological events occurring in early embryogenesis. Among several signalling pathways and inductive factors, the fibroblast growth factors (FGFs) and their receptors (FGFRs) have been shown to be important during early embryogenesis. Previously it has been shown that ESCs expressing a mutant form of FGFR failed to form the two characteristic cell layers of EBs: the endoderm and the ectoderm. In addition, due to the impaired FGF/FGFR signalling, the mutant EBs failed to synthesize laminin-111 and collagen type IV, the main building blocks of the basement membrane (BM) protein network. The aim of this thesis was to elucidate the molecular and biological changes occurring due to impaired FGF/FGFR signalling in differentiating EBs. A large scale microarray study was performed that provided insights into the global gene expression changes occurring in both wild-type (normal) and FGF/FGFR signalling deficient EBs, which resulted in an extensive catalogues of significantly expressed genes in both cell lines. Results showed that during wild-type EB differentiation a rapid down-regulation of pluripotency related genes and up-regulation of genes related to morphogenesis and development occurred. Analysis of FGF/FGFR deficient EBs showed a significant decrease of genes encoding endodermal and BM related proteins. In addition, an increase of mesodermal and pluripotency related gene transcripts was observed. Such transcripts are normally activated later during EB development. The assumption was that the most significantly decreased genes could be involved in FGF/FGFR signalling. To further test this theory, we chose to elucidate the expression pattern of the hitherto uncharacterized gene 1110032E23Rik whose expression was significantly decreased in FGF/FGFR mutant EBs. By in situ hybridization analysis, the expression of 1110032E23Rik was examined in both mouse and Xenopus laevis (frog) embryonic development. Results showed that the expression of 1110032E23Rik in mouse embryos was restricted to epithelia such as the lining of the gastrointestinal tract, urogenital tract, heart, skin and lens, and in addition to the peripheral nervous tissues. Expression analysis of the mouse 1110032E23Rik orthologue in frog embryos showed that mice and frogs share several expression domains such as the eye, heart, kidney and epidermis. The expression was observed at locations where active FGF/FGFR signalling takes place and BMs are present. Based on the expression pattern observed in mice, we named this uncharacterized gene Ened (Expressed in Nerve and Epithelium during Development).
|
|
| 3. |
- Gustafsson, Renata, et al.
(author)
-
Gene expression profiling of differentiating embryonic stem cells expressing dominant negative fibroblast growth factor receptor 2.
- 2007
-
In: Matrix Biology. - : Elsevier BV. - 1569-1802 .- 0945-053X. ; 26, s. 197-205
-
Journal article (peer-reviewed)abstract
- Embryonic stein (ES) cells are derived from the inner cell mass of the blastocyst and can be cultured as three-dimensional embryoid bodies (EBs) in which embryonic pregastrulation stages are faithfully mimicked. Fibroblast growth factor receptors (mainly FGFR2) are involved in the first differentiation events during early mammalian embryogenesis. It has been demonstrated that the presence of FGFR2 is a prerequisite for laminin-111 and collagen type IV synthesis and subsequently basement membrane formation in EBs. To identify genes that are influenced by FGFR signalling, we performed global gene expression profiling of differentiating EBs expressing dominant negative FGFR2 (dnFGFR2), acquiring an extensive catalogue of down- and up-regulated genes. We show a strong down-regulation of endodermal and basement membrane related genes, which strengthen the view that the FGFR signalling pathway is a main stimulator of basement membrane synthesis in EBs. We further present down-regulation of genes previously not linked to FGFR signalling, and in addition an active transcription of some mesodermal related genes in differentiating dnFGFR2 EBs.
|
|
| 4. |
- Häger, Mattias, et al.
(author)
-
Cib2 binds integrin a7Bb1D and is reduced in laminin a2 chain deficient muscular dystrophy
- 2008
-
In: Journal of Biological Chemistry. - 1083-351X. ; 283:36, s. 24760-24769
-
Journal article (peer-reviewed)abstract
- Mutations in the gene encoding laminin alpha 2 chain cause congenital muscular dystrophy type 1A. In skeletal muscle, laminin alpha 2 chain binds at least two receptor complexes: the dystrophin-glycoprotein complex and integrin alpha 7 beta 1. To gain insight into the molecular mechanisms underlying this disorder, we performed gene expression profiling of laminin alpha 2 chain-deficient mouse limb muscle. One of the down-regulated genes encodes a protein called Cib2 (calcium-and integrin-binding protein 2) whose expression and function is unknown. However, the closely related Cib1 has been reported to bind integrin alpha IIb and may be involved in outside-in-signaling in platelets. Since Cib2 might be a novel integrin alpha 7 beta 1-binding protein in muscle, we have studied Cib2 expression in the developing and adult mouse. Cib2 mRNA is mainly expressed in the developing central nervous system and in developing and adult skeletal muscle. In skeletal muscle, Cib2 colocalizes with the integrin alpha 7B subunit at the sarcolemma and at the neuromuscular and myotendinous junctions. Finally, we demonstrate that Cib2 is a calcium-binding protein that interacts with integrin alpha 7B beta 1D. Thus, our data suggest a role for Cib2 as a cytoplasmic effector of integrin alpha 7B beta 1D signaling in skeletal muscle.
|
|
