Migrasomes, a novel organelle first reported by Professor Li Yu’ s team in 2015, are vesicular structures with diameters ranging from 0.5 to 3 micrometers that form on the retraction fibers at the rear of migrating cells. These structures contain various biomolecules such as proteins, nucleic acids, and lipids, along with numerous small vesicles, each approximately 50 nanometers in diameter. Migrasomes act as conduits for information and material exchange between cells and their microenvironments, participating in essential physiological and pathological processes such as embryonic development, angiogenesis, immune responses, and tumorigenesis. In recent years, as the mechanisms and biological functions of migrasomes have been elucidated, a methodological framework for studying migrasomes has gradually emerged, laying the foundation for further research advancements.
Migrasomes possess a distinctive morphology and have a lifespan of several hours, making them well-suited for high-quality optical microscopy imaging. Therefore, optical imaging systems have become the most direct and reliable method for detecting and analyzing migrasomes. Based on published studies and the authors’ own research experiences, this article outlines a protocol for observing migrasomes using optical microscopy. It also summarizes the information on proteins, dyes, and antibodies that can be used to label migrasomes, and details the steps for constructing an in vitro migrasome reconstitution system. These protocols provide a basic operational guide for high-quality migrasome observation. However, given the diversity of research objectives and the complexity of migrasomes, the authors recommend that researchers may need to tailor the experimental procedures to their specific needs. As our understanding of migrasomes deepens and technologies evolve, the methodologies for migrasome imaging are expected to be continuously updated, thereby facilitating further advances in migrasome biology. The work entitled “Seeing is believing: observation of migrasomes” was published on Biophysics Reports (published on February 2, 2024).
Image:Migrasome images of Tetraspanin4-GFP over-expressed L929 cells were collected by confocal microscopy at a proper focal plane or improper (Upper or Lower) focal plane. Scale bar, 10 m.
Reference: Yuwei, H. and Y. Li (2024). "Seeing is believing: observation of migrasomes." Biophysics Reports 9: 1-15. http://www.biophysics-reports.org/en/article/doi/10.52601/bpr.2023.230024
Key points:
Step-by-step Procedure
l Cell culture protocol for migrasome observation.
l Labeling of migrasomes using fluorescent proteins, dyes, and antibodies.
l Purification and insertion of proteins onto liposomes for in vitro reconstitution.
l Imaging of migrasomes and statistical analysis.
Advantages and Limitations
Ø Standardized protocol for observing migrasomes.
Ø Provides analysis of migrasome characteristics and supports biogenesis research.
Ø In vitro system offers new perspectives on migrasome formation mechanisms.
Ø Statistical methods provide objective judgments on impacts on migrasomes.
About Biophysics Reports
Biophysics Reports is an international, open-access journal that serves as a worldwide forum, which publishes novel theories, methods, and protocols, as well as significant improvements in basic research techniques across multidisciplinary areas of the biological and biomedical sciences. The article types include: Commentaries, Methods, Protocols, Research articles, and Reviews.The Editor-in-Chief is Academician Tao Xu from Institute of Biophysics, Chinese Academy of Sciences (CAS). Biophysics Reports has been indexed by PubMed Central, SCOPUS, CSCD etc.