Investigation of Platelet-Derived Growth Factors in Zebrafish Kupffer’s Vesicle

Abstract

Plate-derived growth factors (PDGFs) are mitogenic signaling proteins that demonstrate extensive role in cellular activity as one of the first characterized growth factors. Their signaling pathway is critical throughout animal development, driving mesenchymal proliferation and cell migration in the early developmental stages as well as inducing cellular differentiation and tissue remodeling in more mature stages. Among numerous studies that have revealed the function of PDGF in various contexts, Liu et al. showed expression of pdgf-a and pdgfr-a in zebrafish Kupffer’s vesicle (KV) during late gastrulation and early somite stages. Our study attempts to take this expression into further investigation and find out whether pdgf-a and pdgfr-a show functional significance associated with KV. Considering the nature of PDGF signaling that induces various cellular movements, it seemed plausible that this gene plays important role in KV morphogenesis, cilia formation in KV, or signaling of Nodal genes that regulate left-right asymmetry. However, the results from this study rather reveal fundamental difference from Liu’s paper and suggest that the expression of pdgf-a and pdgfr-a in KV is questionable. While this study accounts for several factors that lead to the evident discrepancy between previous work and current data, it also reconfirms other characteristic features of KV through RT-PCR and in situ hybridization. Moreover, these results propose future directions through which PDGF could be further characterized, and eventually enhance understanding of this complex,elusive, multifaceted gene.