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Acknowledgements

We thank Dr. Kimitsune Ishizaki for providing the histone H2B-tdTomato entry vector

and Dr. Yuichiro Watanabe, Dr. Takahiro Hamada, Mr. Kazutaka Futagami, and Ms.

Sakiko Ishida for technical support with transformation of M. polymorpha. This research

was supported by MXT/JSPS KAKENHI 18K14743 and 21K06247 to Y. Sakamoto,

20H04884 to R.N., and 19H03259, 20H03297, and 20H05911 to S.M. Y. Sakamoto is also

supported by the Osaka University Program for the Support of Networking among

Present and Future Researchers, and S.M. is also supported by the Mitsubishi Foundation. We thank Edanz (https://jp.edanz.com/ac) for editing a draft of this manuscript.

Author contributions

Y. Sakamoto and S.M. designed the research; Y. Sakamoto, A.I., Y. Sakai, M.S., R.N., K.A.,

and Y. Sano performed the research; Y. Sakamoto and A.I. analyzed the data; Y. Sakamoto, Y. Sano, T.F., H.T., T.K., and S.M. wrote the paper.

Competing interests

The authors declare the following competing interests: the patent application in Japan.

Patent applicant: Tokyo University of Science, Inventors: Yuki Sakamoto and Sachihiro

Matsunaga, Application No.: 2020-026975, Status: pending. Yuki Sakamoto and Sachihiro Matsunaga are unpaid advisory positions of plant tissue-clearing reagents in Tokyo

Chemical Industry Cooperation (Tokyo, Japan). The remaining authors declare no

competing interests.

Additional information

Supplementary information The online version contains supplementary material

available at https://doi.org/10.1038/s42003-021-02955-9.

Correspondence and requests for materials should be addressed to Sachihiro Matsunaga.

Peer review information Communications Biology thanks Sunghoe Chang, Irene

Costantini, and Noriko Inada for their contribution to the peer review of this work.

Primary Handling Editors: Chao Zhou and Caitlin Karniski. Peer reviewer reports are

available.

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