title: Smad-interacting protein-1 and microRNA 200 family define a nitric oxide-dependent molecular circuitry involved in embryonic stem cell mesendoderm differentiation.
abstract: OBJECTIVE
  Smad-interacting protein-1 (Sip1/ZEB2) is a transcriptional repressor of the telomerase reverse transcriptase catalytic subunit (Tert) and has recently been identified as a key regulator of embryonic cell fate with a phenotypic effect similar, in our opinion, to that reported for nitric oxide (NO). Remarkably, SIP1/ZEB2 is a known target of the microRNA 200 (miR-200) family. In this light, we postulated that Sip1/ZEB2 and the miR-200 family could play a role during the NO-dependent differentiation of mES.
  
  
  RESULTS
  The results of the present study show that Sip1/ZEB2 expression is downregulated during the NO-dependent expression of mesendoderm and early cardiovascular precursor markers, including Flk1 and CXCR4 in mES. Coincidently, members of the miR-200 family, namely miR-429, -200a, -200b, and -200c, were transcriptionally induced in parallel to mouse Tert. This regulation occurred at the level of chromatin. Remarkably, miR-429/miR-200a overexpression or Sip1/ZEB2 knockdown by short hairpin RNA interference elicited a gene expression pattern similar to that of NO regardless of the presence of leukemia inhibitory factor.
  
  
  CONCLUSIONS
  These results are the first demonstrating that the miR-200 family and Sip1/ZEB2 transcription factor are regulated by NO, indicating an unprecedented molecular circuitry important for telomerase regulation and early differentiation of mES.
authors.affiliation: Laboratorio di Patologia Vascolare, Istituto Dermopatico dell'Immacolata-IRCCS, Rome, Italy.
authors.forename: Jessica
authors.initials: J
authors.lastname: Rosati
authors.forename: Francesco
authors.initials: F
authors.lastname: Spallotta
authors.forename: Simona
authors.initials: S
authors.lastname: Nanni
authors.forename: Annalisa
authors.initials: A
authors.lastname: Grasselli
authors.forename: Annalisa
authors.initials: A
authors.lastname: Antonini
authors.forename: Sara
authors.initials: S
authors.lastname: Vincenti
authors.forename: Carlo
authors.initials: C
authors.lastname: Presutti
authors.forename: Claudia
authors.initials: C
authors.lastname: Colussi
authors.forename: Carmen
authors.initials: C
authors.lastname: D'Angelo
authors.forename: Anna
authors.initials: A
authors.lastname: Biroccio
authors.forename: Antonella
authors.initials: A
authors.lastname: Farsetti
authors.forename: Maurizio C
authors.initials: MC
authors.lastname: Capogrossi
authors.forename: Barbara
authors.initials: B
authors.lastname: Illi
authors.forename: Carlo
authors.initials: C
authors.lastname: Gaetano
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D042002:Chromatin Assembly and Disassembly; D053595:Embryonic Stem Cells / Q000187:drug effects / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D053605:Leukemia Inhibitory Factor / Q000378:metabolism; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D019098:Telomerase / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic; D014162:Transfection; D000074165:Zinc Finger E-box Binding Homeobox 2
chemical_list: D018398:Homeodomain Proteins; D053605:Leukemia Inhibitory Factor; D035683:MicroRNAs; C543719:Mirn200 microRNA, mouse; D020030:Nitric Oxide Donors; D012333:RNA, Messenger; D012097:Repressor Proteins; C120602:ZEB2 protein, mouse; D000074165:Zinc Finger E-box Binding Homeobox 2; D009569:Nitric Oxide; D019098:Telomerase; C509187:Tert protein, mouse