title: The 3T3-L1 fibroblast to adipocyte conversion is accompanied by increased expression of angiopoietin-1, a ligand for tie2.
abstract: The tie2 receptor tyrosine kinase plays a key role in angiogenesis, and the remodeling and maturation of blood vessels. In this study we have used a factor-dependent cell line (Ba/F3) expressing a chimeric receptor containing the extracellular domain of mouse tie2 and the transmembrane and cytoplasmic domain of the erythropoietin receptor to identify specific binding activity associated with an adipogenic sub-line of 3T3 fibroblasts (3T3-L1). 3T3-L1 fibroblasts are capable of undergoing differentiation to adipocytes under specific culture conditions. When compared to 3T3-L1 cells, the adipocyte differentiated cultures, which contain both pre-adipocytes and adipocytes, exhibited a significantly increased ability to support the growth of Ba/F3 cells expressing the chimeric receptor. Using probes specific for two recently described ligands for tie2, Ang-1 and Ang-2, we have shown that mRNA encoding Ang-1 is upregulated when 3T3-L1 fibroblasts are differentiated to adipocytes. These results suggest that the levels of Ang-1 protein and mRNA in 3T3-L1 cells can be regulated by cellular differentiation in adipose development.
authors.affiliation: Ludwig Institute for Cancer Research, Royal Melbourne Hospital, Victoria, Australia. Steven.stacker@ludwig.edu.au
authors.forename: S A
authors.initials: SA
authors.lastname: Stacker
authors.forename: A S
authors.initials: AS
authors.lastname: Runting
authors.forename: C
authors.initials: C
authors.lastname: Caesar
authors.forename: A
authors.initials: A
authors.lastname: Vitali
authors.forename: M
authors.initials: M
authors.lastname: Lackmann
authors.forename: J
authors.initials: J
authors.lastname: Chang
authors.forename: L
authors.initials: L
authors.lastname: Ward
authors.forename: A F
authors.initials: AF
authors.lastname: Wilks
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D016475:3T3 Cells; D017667:Adipocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D042683:Angiopoietin-1; D042702:Angiopoietin-2; D000818:Animals; D000911:Antibodies, Monoclonal; D001483:Base Sequence; D001681:Biological Assay; D002454:Cell Differentiation / Q000187:drug effects; D017931:DNA Primers / Q000235:genetics; D003907:Dexamethasone / Q000494:pharmacology; D005260:Female; D005347:Fibroblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D007328:Insulin / Q000494:pharmacology; D008024:Ligands; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D010641:Phenotype; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000276:immunology / Q000378:metabolism; D042787:Receptor, TIE-2; D015854:Up-Regulation
chemical_list: D042683:Angiopoietin-1; D042702:Angiopoietin-2; C467628:Angpt1 protein, mouse; D000911:Antibodies, Monoclonal; D017931:DNA Primers; D007328:Insulin; D008024:Ligands; D008562:Membrane Glycoproteins; D011506:Proteins; D012333:RNA, Messenger; D003907:Dexamethasone; D020794:Receptor Protein-Tyrosine Kinases; D042787:Receptor, TIE-2; D015056:1-Methyl-3-isobutylxanthine