Study on the novel regulator of BMP signaling during Xenopus embryonic development

Abstract

The intricate process of vertebrate embryogenesis, particularly in regard to dorsoventral patterning and axis formation, is orchestrated by the vertebrate organizer. Despite extensive research on cellular signaling pathways governing organizer function, our understanding remains incomplete, leaving still unknown pathways to explore. In this study, I aimed to identify new potential key factors within the organizer and investigate their roles, shedding light on the regulatory molecular mechanisms governing organizer function. In the first part of the study, Xenopus laevis tissue mimicking the organizer was utilized to perform cDNA microarray analysis. The comprehensive analysis of the result unveiled a promising list of prospective genes expressed in the organizer. In the second part of the study, I characterized the six-transmembrane domain containing transmembrane protein 150b (Tmem150b) during Xenopus development. I determined the expression pattern of Tmem150b within the organizer region and its induction by Activin/Nodal signaling, solidifying its significance in the context of embryonic development. In the third part of the study, I demonstrated the bone morphogenetic protein (BMP) antagonizing effect of Tmem150b. Perturbing Tmem150b through knockdown experiments in Xenopus resulted in notable phenotype abnormalities, such as head defects and a shortened body axis. Further investigation revealed Tmem150b negatively regulates BMP signaling, potentially through its physical interaction with activin receptor-like kinase 2 (ALK2). Collectively, this study has provided valuable insights into the regulatory mechanisms governing BMP signaling and axis formation in vertebrate embryogenesis, with a specific focus on the novel regulator Tmem150b within the organizer. Furthermore, the cDNA microarray analysis presented numerous other candidate genes, offering prospects for future investigations and a deeper understanding of the genetic networks associated with the organizer during vertebrate embryogenesis.