Immunolocalization of an FGF-binding protein reveals a widespread expression pattern during different stages of mouse embryo development.
Fibroblast growth factors (FGFs) play important roles during fetal and embryonic development. FGF-2 (basic FGF, bFGF) is widely expressed in the embryo and has been linked to tissue growth and remodeling. However, it is tightly bound to heparin sulfate proteoglycans of the extracellular matrix which quenches its biological activity. We showed previously that a secreted FGF-binding protein (FGF-BP) can mobilize and activate FGF-2 from the extracellular matrix. While considerable data exist on the expression and pivotal role of FGF-BP in tumor growth, less is known about FGF-BP during embryonic development. In this immunohistochemical study in mice, we show FGF-BP protein expression in a broad spectrum of tissues at various stages between day 8 and day 16 of embryonal development, and compare FGF-BP and FGF-2 immunolocalization. FGF-BP is detected in the digestive system, thymus, skin, hair follicles, dental germ, respiratory tract, various glandular tissues, kidney, liver, and certain areas of the CNS, with immunoreactivity being mainly confined to cells of primitive epithelia. The putative significance of these findings with regard to mobilization of FGF-2 or other molecules is discussed. From the locally confined, time-dependent, and apparently tightly regulated FGF-BP expression we propose that FGF-BP may play an important role in embryonic development.
Aigner
Achim
A
Department of Pharmacology and Toxicology, Philipps University, School of Medicine, Karl-von-Frisch-Strasse 1, 35033 Marburg, Germany. aigner@mailer.uni-marburg.de
Ray
Patricio E
PE
Czubayko
Frank
F
Wellstein
Anton
A
D000311:Adrenal Glands / Q000737:chemistry / Q000196:embryology; D000818:Animals; D000915:Antibody Affinity; D000918:Antibody Specificity; D001842:Bone and Bones / Q000737:chemistry / Q000196:embryology; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000276:immunology; D002490:Central Nervous System / Q000737:chemistry / Q000196:embryology; D004064:Digestive System / Q000737:chemistry / Q000196:embryology; D004622:Embryo, Mammalian / Q000737:chemistry*; D016222:Fibroblast Growth Factor 2 / Q000032:analysis; D018859:Hair Follicle / Q000737:chemistry / Q000196:embryology; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins; D047908:Intracellular Signaling Peptides and Proteins; D007668:Kidney / Q000737:chemistry / Q000196:embryology; D051379:Mice; D018482:Muscle, Skeletal / Q000737:chemistry / Q000196:embryology; D009206:Myocardium / Q000737:chemistry; D012137:Respiratory System / Q000737:chemistry / Q000196:embryology; D012867:Skin / Q000737:chemistry / Q000196:embryology; D013997:Time Factors; D014070:Tooth / Q000737:chemistry / Q000196:embryology; D001743:Urinary Bladder / Q000737:chemistry / Q000196:embryology
D002352:Carrier Proteins; C489453:Fgfbp1 protein, mouse; D036341:Intercellular Signaling Peptides and Proteins; D047908:Intracellular Signaling Peptides and Proteins; D016222:Fibroblast Growth Factor 2