title: PKA/CREB signaling triggers initiation of endothelial and hematopoietic cell differentiation via Etv2 induction.
abstract: Ets family protein Etv2 (also called ER71 or Etsrp) is a key factor for initiation of vascular and blood development from mesodermal cells. However, regulatory mechanisms and inducing signals for Etv2 expression have been largely unknown. Previously, we revealed that cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) signaling enhanced differentiation of vascular progenitors into endothelial cells (ECs) and hematopoietic cells (HPCs) using an embryonic stem cell (ESC) differentiation system. Here, we show that PKA activation in an earlier differentiation stage can trigger EC/HPC differentiation through Etv2 induction. We found Etv2 was markedly upregulated by PKA activation preceding EC and HPC differentiation. We identified two cAMP response element (CRE) sequences in the Etv2 promoter and 5'-untranslated region and confirmed that CRE-binding protein (CREB) directly binds to the CRE sites and activates Etv2 transcription. Expression of a dominant negative form of CREB completely inhibited PKA-elicited Etv2 expression and induction of EC/HPCs from ESCs. Furthermore, blockade of PKA significantly inhibited Etv2 expression in ex vivo whole-embryo culture using Etv2-Venus knockin mice. These data indicated that PKA/CREB pathway is a critical regulator for the initiation of EC/HPC differentiation via Etv2 transcription. This early-stage molecular linkage between a triggering signal and transcriptional cascades for differentiation would provide novel insights in vascular and blood development and cell fate determination.
authors.affiliation: Laboratory of Stem Cell Differentiation, Stem Cell Research Center, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan; Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Yamamizu
authors.forename: Taichi
authors.initials: T
authors.lastname: Matsunaga
authors.forename: Shiori
authors.initials: S
authors.lastname: Katayama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kataoka
authors.forename: Naoya
authors.initials: N
authors.lastname: Takayama
authors.forename: Koji
authors.initials: K
authors.lastname: Eto
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Nishikawa
authors.forename: Jun K
authors.initials: JK
authors.lastname: Yamashita
mesh_terms: D020121:5' Untranslated Regions / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D002454:Cell Differentiation; D002460:Cell Line; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism; D053595:Embryonic Stem Cells / Q000166:cytology / Q000201:enzymology; D042783:Endothelial Cells / Q000166:cytology* / Q000378:metabolism; D004789:Enzyme Activation; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D008954:Models, Biological; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D050784:Proto-Oncogene Protein c-ets-1 / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D015398:Signal Transduction; D046509:Tissue Culture Techniques; D014158:Transcription, Genetic
chemical_list: D020121:5' Untranslated Regions; D017362:Cyclic AMP Response Element-Binding Protein; D050784:Proto-Oncogene Protein c-ets-1; D034741:RNA, Small Interfering; D017868:Cyclic AMP-Dependent Protein Kinases