Search Results
You are looking at 1 - 2 of 2 items for
- Author: YQ Zhang x
- Refine by access: All content x
Search for other papers by M Wankell in
Google Scholar
PubMed
Search for other papers by S Kaesler in
Google Scholar
PubMed
Search for other papers by YQ Zhang in
Google Scholar
PubMed
Search for other papers by C Florence in
Google Scholar
PubMed
Search for other papers by S Werner in
Google Scholar
PubMed
Search for other papers by R Duan in
Google Scholar
PubMed
Follistatin is a secreted protein that binds activin in vitro and in vivo and thereby inhibits its biological functions. Recently, related human and murine genes, designated follistatin-related gene (FLRG), were identified, and their products were shown to bind activin with high affinity. In this study we further characterized the murine FLRG protein, and we analyzed its tissue-specific expression and regulation in comparison with those of follistatin. Transient expression of the mouse FLRG protein in COS-1 cells revealed that the FLRG cDNA encodes a secreted glycoprotein. FLRG mRNA was expressed at high levels in the lung, the testis, the uterus and, particularly, the skin. Immunohistochemistry revealed the presence of FLRG in the basement membrane between the dermis and the epidermis and around blood vessels. FLRG mRNA expression was induced in keratinocytes by keratinocyte growth factor, epidermal growth factor and transforming growth factor-beta 1, and in fibroblasts by platelet-derived growth factor and epidermal growth factor. The induction was more rapid, but weaker, than that of follistatin. Most interestingly, both follistatin and FLRG were expressed during the wound healing process, but their distribution within the wound was different. The different expression pattern of FLRG and follistatin and their differential regulation suggest different functions of these activin-binding proteins in vivo.
Laboratoire de Biologie de la Differentation et du Development, Universite Victor Segalen Bordeaux 2, 146 rue Leo Saignat 33076 Bordeaux cedex, France
Search for other papers by A G Kayali in
Google Scholar
PubMed
Laboratoire de Biologie de la Differentation et du Development, Universite Victor Segalen Bordeaux 2, 146 rue Leo Saignat 33076 Bordeaux cedex, France
Search for other papers by A Stotland in
Google Scholar
PubMed
Laboratoire de Biologie de la Differentation et du Development, Universite Victor Segalen Bordeaux 2, 146 rue Leo Saignat 33076 Bordeaux cedex, France
Search for other papers by K V Gunst in
Google Scholar
PubMed
Laboratoire de Biologie de la Differentation et du Development, Universite Victor Segalen Bordeaux 2, 146 rue Leo Saignat 33076 Bordeaux cedex, France
Search for other papers by M Kritzik in
Google Scholar
PubMed
Laboratoire de Biologie de la Differentation et du Development, Universite Victor Segalen Bordeaux 2, 146 rue Leo Saignat 33076 Bordeaux cedex, France
Search for other papers by G Liu in
Google Scholar
PubMed
Laboratoire de Biologie de la Differentation et du Development, Universite Victor Segalen Bordeaux 2, 146 rue Leo Saignat 33076 Bordeaux cedex, France
Search for other papers by S Dabernat in
Google Scholar
PubMed
Laboratoire de Biologie de la Differentation et du Development, Universite Victor Segalen Bordeaux 2, 146 rue Leo Saignat 33076 Bordeaux cedex, France
Search for other papers by Y-Q Zhang in
Google Scholar
PubMed
Laboratoire de Biologie de la Differentation et du Development, Universite Victor Segalen Bordeaux 2, 146 rue Leo Saignat 33076 Bordeaux cedex, France
Search for other papers by W Wu in
Google Scholar
PubMed
Laboratoire de Biologie de la Differentation et du Development, Universite Victor Segalen Bordeaux 2, 146 rue Leo Saignat 33076 Bordeaux cedex, France
Search for other papers by N Sarvetnick in
Google Scholar
PubMed
Activated signaling proteins regulate diverse processes, including the differentiation of the pancreatic islet cells during ontogeny. Here we uncover the in vivo phosphorylation status of major growth factor-activated signaling proteins in normal adult mice and during pancreatic islet regeneration. We report elevated phospho-mitogen-activated protein kinase (phospho-MAPK), phospho-c-Jun-NH2-terminal kinase (phospho-JNK), and phospho-p38 MAPK expression during pancreatic regeneration. Immunoblotting experiments demonstrated elevated phosphorylation of p52 Src-homology/collagen (SHC) in the ductal network as well, substantiating the activation of this pathway. Furthermore, protein kinase B (PKB/Akt), a key signaling protein in the anti-apoptotic pathway, was phosphorylated to a greater extent in the ductal network from regenerating pancreas. We observed fibroblast growht factor (FGF)10 and platelet-derived growth factor (PDGF)AA expression in embryonic as well as regenerating adult pancreas. Epidermal growth factor (EGF) and PDGFAA stimulated MAPK and Akt phosphorylation, while FGF10 stimulated MAPK but not Akt phosphorylation in a time-dependent manner in freshly isolated cells from the adult ductal network. These data suggest that a heightened level of expression and stimulation of key signaling proteins underlie the expansion and differentiation processes that support pancreatic ontogeny and regeneration.
