Guzman-Espinoza Mariann, Vander Wende Helen M, Pacheco Jessica L, Roldán Alejandra Olano, Hutchins Erica J
Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA; Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA.
Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA; Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA; Oral and Craniofacial Sciences Graduate Program, School of Dentistry, University of California San Francisco, San Francisco, CA, USA.
Differentiation. 2025 Jul-Aug;144:100883. doi: 10.1016/j.diff.2025.100883. Epub 2025 Jun 23.
Neural crest cells are multipotent cells present in vertebrate embryos that give rise to a wide array of cell types and tissues. A growing number of studies have identified post-transcriptional regulatory events that are essential for multiple stages of neural crest development, though a thorough characterization of the post-transcriptional regulators controlling these events is currently lacking. From single cell RNA-sequencing data, we identified members of the Pumilio family of RNA-binding proteins, PUM1 and PUM2, as candidate post-transcriptional regulators of neural crest development. Using hybridization chain reaction (HCR) in avian embryos (Gallus gallus), we characterized the spatiotemporal expression of Pumilio family mRNAs during early stages of cranial neural crest development. We show that Pum1 and Pum2, though expressed throughout the three germ layers, were enriched in ectodermally-derived tissues, and following neurulation, Pum1 and Pum2 show distinct expression patterns. We observed that Pum1 displayed a more uniform expression throughout the neural tube and neural crest during neural crest specification and the epithelial-mesenchymal transition (EMT). In contrast, Pum2 was enriched in neural crest cells poised to undergo EMT. We thus hypothesize that PUM1 and PUM2, often speculated to be functionally redundant, may play distinct roles at key steps of neural crest development.
神经嵴细胞是脊椎动物胚胎中存在的多能细胞，可分化为多种细胞类型和组织。越来越多的研究已经确定了转录后调控事件，这些事件对神经嵴发育的多个阶段至关重要，尽管目前缺乏对控制这些事件的转录后调节因子的全面表征。从单细胞RNA测序数据中，我们确定了RNA结合蛋白Pumilio家族的成员PUM1和PUM2，作为神经嵴发育的候选转录后调节因子。利用鸡胚（Gallus gallus）中的杂交链式反应（HCR），我们表征了颅神经嵴发育早期阶段Pumilio家族mRNA的时空表达。我们发现，虽然Pum1和Pum2在三个胚层中均有表达，但在外胚层来源的组织中富集，并且在神经胚形成后，Pum1和Pum2表现出不同的表达模式。我们观察到，在神经嵴特化和上皮-间充质转化（EMT）过程中，Pum1在整个神经管和神经嵴中表现出更均匀的表达。相比之下，Pum2在准备进行EMT的神经嵴细胞中富集。因此，我们推测通常被认为功能冗余的PUM1和PUM2可能在神经嵴发育的关键步骤中发挥不同的作用。
