Experience report of Hands-on Training Program E: Exploring multi-cellular mechanics

 Introduction

My name is Asuka Takeda-Sakazume, a postdoctoral researcher at Ochanomizu University. I am grateful for the opportunity to participate in the Hands-on Training Program E: Exploring multi-cellular mechanics, as well as for the chance to write this article. My career trajectory has been distinctive. After completing my master’s degree, I initially worked in the private sector, stepping away from academia. Following approximately five years of industry experience, I re-entered academia for my doctoral studies under the guidance of Professor Yoshihiro Mogami (Ochanomizu University). During my doctoral program, I experienced significant life events, including pregnancy and childbirth of three children and accompanying my husband on an overseas posting. Despite these challenges, I successfully obtained my doctorate two years ago. Consequently, although my biological age does not align with typical early career researchers (my mental age feels like I am in my 20s), I was nonetheless given the opportunity to participate in this training program. I extend my heartfelt thanks to the Biophysical Society for its generosity. While I apologize for any shortcomings in my writing, I hope that my thoughts, as expressed here, will provide valuable insights for those considering hosting or participating in future training programs.

 The reason I applied to the training program

During my master’s studies, I investigated the gravitaxis of Paramecium caudatum, sparking my interest in how cells sense and respond to force. This fascination continued during my doctoral research on the gravitaxis of coral larvae, a topic I am still exploring with the support of a research grant. Coral larvae exhibit unique gravitaxis behaviors not observed in other aquatic microorganisms, suggesting mechanisms involving the position of the center of gravity, morphology, and linkage between gravity-sensing and ciliary movement. I applied for the training program, which emphasizes the mechanics of multicellular systems, in the hope of uncovering further insights into these mechanisms. My primary research method involves filming and analyzing the behaviors of organisms in order to extract biophysical parameters such as swimming speed, morphology, and spatial position. Maintaining the biological samples in a living state and designing equipment tailored to my observational needs are daily priorities for me. I therefore have a strong interest in bioimaging technology, which also motivated my application for this program.

 After participating in the training program

This hands-on experience was highly rewarding for me. I gained insights from frontline professors on my current research, learned about the latest advances in knowledge, technology, and equipment, and expanded my horizons. Additionally, I feel the immense value of the connections that I made with the instructors and other participants.

Dr. Masafumi Inaba (assistant professor at Kyoto University), who led the morning program, is researching the peristaltic movement of chicken embryo intestines. I was familiar with the professor’s work from the literature while analyzing the peristaltic movement of a new sea anemone species with my laboratory student. Discovering that Dr. Inaba would be the lecturer was both surprising and delightful. During the session, we performed a series of experiments, starting with dissecting a chicken embryo to remove the cecum; observing and photographing its peristaltic movement; creating a kymograph using analysis software; and extracting biophysical parameters. The experience of inserting scissors into a living embryo with a beating heart evoked a profound sense of life’s fragility and gratitude. Although we faced challenges, such as accidentally cutting the cecal tissue or taking too long to observe significant peristaltic movement, Dr. Inaba encouraged us with the advice: “You can practice many times.” I was also impressed by Dr. Inaba’s use of a 3D printer to create an observation container optimally shaped for the sample. This innovative approach is something I would like to apply to my current research. Engaging directly with the experimental procedures described in reference papers deepened my understanding. The method of creating a kymograph and extracting parameters such as wavelength, period, and propagation speed of peristaltic waves closely aligned with my research on sea anemone peristalsis. Receiving direct instruction on identifying the pacemaker’s position was particularly beneficial.

Dr. Takafumi Ichikawa (assistant professor at Kyoto University), who led the afternoon program, has developed a 3D imaging technique combining light-sheet microscopy and live-cell high-speed atomic force microscopy (AFM) to study the early development of mouse embryos. I eagerly anticipated learning about this technology that enables 3D observation of embryos on this scale. In the lecture preceding the practical session, the statement “Physics helps us understand the phenomenon of life” resonated deeply with me. During the practical, we attempted to transfer mouse embryos into a specialized observation container using a pipette designed to suck out the embryos with our breath. This task proved challenging, as air bubbles formed when we exhaled. Dr. Ichikawa quickly removed the air bubbles, demonstrating his expert technique, which left me in awe. After much effort, we successfully placed the mouse embryos in the container, and it was time to start imaging. The 3D observation device, jointly developed by Dr. Ichikawa and a specialized company, took into account the sensitivity of early mouse embryos to light, and impressed me with its ability to capture clear, continuous 3D images of the embryos’ details. This experience not only expanded my knowledge but also inspired me to consider how this device could advance my own research. Moreover, hearing about the professor’s career path—a subject that is currently a concern of my own, as a postdoctoral researcher—was invaluable.

Throughout the day, experiencing research programs in a different institute from my current affiliation, where I completed my doctoral studies, allowed me to engage in new techniques and discussions, consider collaborative research, and enhance my research skills. Communication with instructors and other participants in English also motivated me to improve my own English skills. Although I participated in the program for only one day with a team of five individuals from diverse fields, we bonded through the program. We shared our research content, positions, future career paths, and the challenges of balancing family and research. This created a harmonious and enjoyable atmosphere throughout the day. I remain in contact with some of the participants, and these connections continue to be a source of encouragement for me.

Acknowledgements

I would like to take this opportunity to express my deepest gratitude to Professor Kumiko Hayashi (The University of Tokyo) for planning Hands-on Training Program E and making all the necessary arrangements; to Associate Professor Shige H. Yoshimura (Kyoto University), who also made all the necessary arrangements and led the participants throughout the day; to Dr. Masafumi Inaba and Dr. Takafumi Ichikawa for training us all with their professional and kind guidance.