Huntsman Cancer Institute, The University of Utah, Salt Lake City, UT, 84112, USA.
Department of Oncological Sciences, The University of Utah, Salt Lake City, UT, 84112, USA.
Sci Rep. 2020 Nov 9;10(1):19303. doi: 10.1038/s41598-020-75774-3.
Platelet Derived Growth Factor Receptor (PDGFR) signaling is a central mitogenic pathway in development, as well as tissue repair and homeostasis. The rules governing the binding of PDGF ligand to the receptor to produce activation and downstream signaling have been well defined over the last several decades. In cultured cells after a period of serum deprivation, treatment with PDGF leads to the rapid formation of dramatic, actin-rich Circular Dorsal Ruffles (CDRs). Using CDRs as a robust visual readout of early PDGFR signaling, we have identified several contradictory elements in the widely accepted model of PDGF activity. Employing CRISPR/Cas9 gene editing to disrupt the Pdgfra gene in two different murine cell lines, we show that in addition to the widely accepted function for PDGFR-beta in CDR formation, PDGFR-alpha is also clearly capable of eliciting CDRs. Moreover, we demonstrate activity for heterodimeric PDGF-AB ligand in the vigorous activation of PDGFR-beta homodimers to produce CDRs. These findings are key to a more complete understanding of PDGF ligand-receptor interactions and their downstream signaling consequences. This knowledge will allow for more rigorous experimental design in future studies of PDGFR signaling and its contributions to development and disease.
血小板衍生生长因子受体 (PDGFR) 信号通路是发育过程中以及组织修复和稳态的中心有丝分裂途径。在过去几十年中,已经很好地定义了 PDGF 配体与受体结合以产生激活和下游信号的规则。在血清剥夺后的培养细胞中,用 PDGF 处理会导致剧烈的富含肌动蛋白的圆形背侧皱襞 (CDR) 的快速形成。我们使用 CDR 作为早期 PDGFR 信号的强大视觉读数,在广泛接受的 PDGF 活性模型中发现了几个矛盾的元素。我们使用 CRISPR/Cas9 基因编辑在两种不同的鼠细胞系中破坏 Pdgfra 基因,结果表明,除了 PDGFR-beta 在 CDR 形成中的广泛接受的功能外,PDGFR-alpha 也显然能够引发 CDR。此外,我们证明了 PDGF-AB 配体的异二聚体在强烈激活 PDGFR-beta 同源二聚体以产生 CDR 中的作用。这些发现对于更完整地理解 PDGF 配体-受体相互作用及其下游信号转导后果至关重要。这一知识将允许在未来的 PDGFR 信号及其对发育和疾病的贡献的研究中进行更严格的实验设计。