miR-27b controls venous specification and tip cell fate.
We discovered that miR-27b controls 2 critical vascular functions: it turns the angiogenic switch on by promoting endothelial tip cell fate and sprouting and it promotes venous differentiation. We have identified its targets, a Notch ligand Delta-like ligand 4 (Dll4) and Sprouty homologue 2 (Spry2). miR-27b knockdown in zebrafish and mouse tissues severely impaired vessel sprouting and filopodia formation. Moreover, miR-27b was necessary for the formation of the first embryonic vein in fish and controlled the expression of arterial and venous markers in human endothelium, including Ephrin B2 (EphB2), EphB4, FMS-related tyrosine kinase 1 (Flt1), and Flt4. In zebrafish, Dll4 inhibition caused increased sprouting and longer intersegmental vessels and exacerbated tip cell migration. Blocking Spry2 caused premature vessel branching. In contrast, Spry2 overexpression eliminated the tip cell branching in the intersegmental vessels. Blockade of Dll4 and Spry2 disrupted arterial specification and augmented the expression of venous markers. Blocking either Spry2 or Dll4 rescued the miR-27b knockdown phenotype in zebrafish and in mouse vascular explants, pointing to essential roles of these targets downstream of miR-27b. Our study identifies critical role of miR-27b in the control of endothelial tip cell fate, branching, and venous specification and determines Spry2 and Dll4 as its essential targets.
Urology Department, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
Dauren
D
Biyashev
Dorina
D
Veliceasa
Jacek
J
Topczewski
Jolanta M
JM
Topczewska
Igor
I
Mizgirev
Elena
E
Vinokour
Alagarsamy L
AL
Reddi
Jonathan D
JD
Licht
Sergei Y
SY
Revskoy
Olga V
OV
Volpert
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D001011:Aorta / Q000166:cytology / Q000378:metabolism; D001158:Arteries / Q000196:embryology* / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D015152:Blotting, Northern; D015153:Blotting, Western; D018827:Carcinoma, Lewis Lung / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002454:Cell Differentiation; D002465:Cell Movement; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology* / Q000378:metabolism; D020869:Gene Expression Profiling; D047908:Intracellular Signaling Peptides and Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D035683:MicroRNAs / Q000502:physiology*; D018919:Neovascularization, Physiologic; D020411:Oligonucleotide Array Sequence Analysis; D017346:Protein Serine-Threonine Kinases; D011554:Pseudopodia / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction; D015027:Zebrafish / Q000196:embryology / Q000235:genetics* / Q000378:metabolism
D048868:Adaptor Proteins, Signal Transducing; D015415:Biomarkers; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D035683:MicroRNAs; C540674:Mirn27 microRNA, mouse; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C064045:delta protein; D017346:Protein Serine-Threonine Kinases; C118389:Spry2 protein, mouse