Distinctive Roles of Canonical and Noncanonical Wnt Signaling in Human Embryonic Cardiomyocyte Development

Abstract

SummaryWnt signaling is a key regulator of vertebrate heart development; however, specific roles for human cardiomyocyte development remain uncertain. Here we use human embryonic stem cells (hESCs) to analyze systematically in human cardiomyocyte development the expression of endogenous Wnt signaling components, monitor pathway activity, and dissect stage-specific requirements for canonical and noncanonical Wnt signaling mechanisms using small-molecule inhibitors. Our analysis suggests that WNT3 and WNT8A, via FZD7 and canonical signaling, regulate BRACHYURY expression and mesoderm induction; that WNT5A/5B, via ROR2 and noncanonical signaling, regulate MESP1 expression and cardiovascular development; and that later in development WNT2, WNT5A/5B, and WNT11, via FZD4 and FZD6, regulate functional cardiomyocyte differentiation via noncanonical Wnt signaling. Our findings confirm in human development previously proposed roles for canonical Wnt signaling in sequential stages of vertebrate cardiomyogenesis, and identify more precise roles for noncanonical signaling and for individual Wnt signal and Wnt receptor genes in human cardiomyocyte development.

Wnt11 regulates cardiac chamber development and disease during perinatal maturation

“…Among the major pathways enriched in the P3 poorly preserved modules, we found that 27 out of 58 Wnt-related genes were regulated in a chamber-specific manner, including components from the canonical and noncanonical signaling pathways (24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35). Remarkably, established inhibitors of canonical β-catenindependent signaling (Wif1, Dkk3, and Sost1) were upregulated in RVs compared with LVs, while several members of the noncanonical Wnt11 signaling (Wnt11, Wnt5a, Ror2, Sfrp5, and Rock2) were enriched in RVs.…”

“…Among the different developmental signals (21)(22)(23), Wnt signaling pathways play prominent roles in cardiac precursor's commitment, cell proliferation, differentiation, and fate (24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35).Actions by the Wnt family molecules can be classified into the canonical Wnt/β-catenin-dependent pathway and the noncanonical pathway, which is generally β-catenin independent, and its function can be mediated by 2 distinct modules of the noncanonical signaling: (a) the planar cell polarity (PCP) pathway; and (b) the Wnt/ Ca 2+ pathway, which involves calmodulin-dependent kinase II (CamKII), protein kinase C (PKC), and calcineurin. These factors may coordinate important cellular signaling processes including regulating the expression of key cell cycle regulators.…”

“…Although substantial overlap exists between the different Wnt signaling pathways during heart development, existing evidence has revealed a critical role of noncanonical Wnt11 in orchestrating early development (24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35). Wnt11 expression is dynamically regulated in a temporal-spatial manner (28), playing important roles in myocardial development, including the second heart field (SHF) derivatives and the outflow tract.…”

“…Wnt11-null mouse fetuses developed conotruncal defects including pulmonary stenosis and double-outlet RV (DORV) (29). Finally, recent evidence suggests that Wnt11 may also drive the late stages of cardiac myogenesis coupled with inhibition of the canonical Wnt/β-catenin (30)(31)(32). However, the functional role of Wnt11 in postnatal heart chamber-specific development has not been demonstrated.…”

Identificação de vias moduladas por microRNAs na diferenciação celular e manutenção da pluripotência em células humanas

“…B.1, C.1, C.2a e C.2b) têm como alvo FZD4 e GSK3, da via WNT, e BMPR, ACVR, receptores de Nodal, da via TGFβ, e assim, propõe-se que o mecanismo de promoção de pluripotência por estes miRNAs se dê pela inativação de sinais de diferenciação por WNT, como a ativação de FZD4 na geração de cardiomiótitos (MAZZOTTA et al, 2016), e por TGFβ, como no efeito pró-diferenciação das BMPs (RICHTER et al, 2014), permitindo somente uma regulação positiva destas vias sobre a pluripotência. Um exemplo prático desta hipótese de mecanismo é a participação do miR-181 na reprogramação por meio da ativação de WNT, levando ao acúmulo de β-catenina nuclear, e inibição da sinalização de TGFβ .…”