Wnt/β-catenin signaling pathway activation is required for proliferation of chicken primordial germ cells in vitro

Abstract

Here, we investigated the role of the Wnt/β-catenin signaling pathway in chicken primordial germ cells (PGCs) in vitro. We confirmed the expression of Wnt signaling pathway-related genes and the localization of β-catenin in the nucleus, revealing that this pathway is potentially activated in chicken PGCs. Then, using the single-cell pick-up assay, we examined the proliferative capacity of cultured PGCs in response to Wnt ligands, a β-catenin-mediated Wnt signaling activator (6-bromoindirubin-3′-oxime [BIO]) or inhibitor (JW74), in the presence or absence of basic fibroblast growth factor (bFGF). WNT1, WNT3A, and BIO promoted the proliferation of chicken PGCs similarly to bFGF, whereas JW74 inhibited this proliferation. Meanwhile, such treatments in combination with bFGF did not show a synergistic effect. bFGF treatment could not rescue PGC proliferation in the presence of JW74. In addition, we confirmed the translocation of β-catenin into the nucleus by the addition of bFGF after JW74 treatment. These results indicate that there is signaling crosstalk between FGF and Wnt, and that β-catenin acts on PGC proliferation downstream of bFGF. In conclusion, our study suggests that Wnt signaling enhances the proliferation of chicken PGCs via the stabilization of β-catenin and activation of its downstream genes.

Osthole stimulates bone formation, drives vascularization and retards adipogenesis to alleviate alcohol‐induced osteonecrosis of the femoral head

“…However, osthole could dose‐dependently reverse the inhibition of ethanol on β‐catenin production in BMSCs (Figure 2B,C). Wnt antagonist JW74 was used to investigate the role of Wnt/β‐catenin signalling pathway in the osteoprotective function of osthole . As shown in Figure 2D and E, JW74 (1 μmol/L) significantly abolished the up‐regulation of β‐catenin when BMSCs were co‐treated with ethanol and osthole.…”

CRISPR/Cas9 gene editing in a chicken model: current approaches and applications

“…Additionally, there are several obstacles to this process, because germ cells are relatively transcriptionally quiescent and prone to switching off transgene expression (Seydoux and Braun 2006). Development of efficient methods for culturing chicken PGCs without the loss of germline competency (Song et al 2014;Naito 2015;Whyte et al 2015;Lee et al 2016) was a milestone that brought more possibilities for genetic modification and precise gene editing. The first transgenic birds were generated using PGCs isolated from chicken embryos (stage 11 H.H.)…”

The early development of germ cells in chicken

“…It has been shown that bFGF plays an essential role in the proliferation and survival of chicken PGCs via the mitogen-activated protein kinase kinase (MEK) / extracellular signal-regulated kinases (ERK) signaling pathway, and helps to maintain telomerase activity, migratory activity, and germline contribution in PGCs cultured for extended periods (Choi et al, 2010;Macdonald et al, 2010). More recent studies have shown that MEK1, AKT (also known as protein kinase B, PKB), and SMAD family member 3 (SMAD-3) signalling is required for PGCs to maintain germline transmission capacity, and that Wnt/b-catenin signalling is required for PGC proliferation in vitro (Whyte et al, 2015;Lee et al, 2016b). Furthermore, it has been reported that stem cell factor 2 (SCF2) derived from chickens has potent and prolonged effects on PGC proliferation via FGF2-and c-KIT-mediated growth signals, and is thus crucial for the maintenance of germ cell characteristics and germ line transmission (Daichi et al, 2016).…”