Remodeling of the pre-existing primitive vasculature is necessary for the formation of a complex branched vascular architecture. However, the factors that modulate these processes are incompletely defined. Previously, we defined the role of microRNAs (miRNAs) in endothelial specification. In the present study, we further examined the
Etv2-Cre
mediated ablation of
Dicer
L/L
and characterized the perturbed vascular patterning in the embryo proper and yolk-sac. We mechanistically defined an important role for
miR-130a
, an Etv2 downstream target, in the mediation of vascular patterning and angiogenesis
in vitro
and
in vivo
. Inducible overexpression of
miR-130a
resulted in robust induction of vascular sprouts and angiogenesis with increased uptake of acetylated-LDL. Mechanistically,
miR-130a
directly regulates
Jarid2
expression by binding to its
3’-UTR
region. CRISPR/Cas9 mediated knockout of
miR-130a
showed increased levels of
Jarid2
in the ES/EB system. Further, the levels of
Jarid2
transcripts were increased in the
Etv2-null
embryos at E8.5. In the
in vivo
settings, injection of
miR-130a
specific morpholinos in zebrafish embryos resulted in perturbed vascular patterning with reduced levels of endothelial transcripts in the
miR-130a
morphants. qPCR and
in situ hybridization
techniques demonstrated increased expression of
jarid2a
in the
miR-130a
morphants
in vivo
. These findings demonstrate a critical role for
Etv2-miR-130a-Jarid2
in vascular patterning both
in vitro
and
in vivo
.
Revealing details: whole mount microRNA in situ hybridization protocol for zebrafish embryos and adult tissues
