Signs of biological activities of 28,000-year-old mammoth nuclei in mouse oocytes visualized by live-cell imaging

• Published in: Scientific Reports
• Main Authors: Yamagata, Kazuo, Nagai, Kouhei, Miyamoto, Hiroshi, Anzai, Masayuki, Kato, Hiromi, Miyamoto, Kei, Kurosaka, Satoshi, Azuma, Rika, Kolodeznikov, Igor I., Protopopov, Albert V., Plotnikov, Valerii V., Kobayashi, Hisato, Kawahara-Miki, Ryouka, Kono, Tomohiro, Uchida, Masao, Shibata, Yasuyuki, Handa, Tetsuya, Kimura, Hiroshi, Hosoi, Yoshihiko, Mitani, Tasuku, Matsumoto, Kazuya, Iritani, Akira
• Format: Text
• Language: English
• Published: Nature Publishing Group UK 2019
• Subjects: Article; permafrost
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6411884/; http://www.ncbi.nlm.nih.gov/pubmed/30858410; https://doi.org/10.1038/s41598-019-40546-1

The 28,000-year-old remains of a woolly mammoth, named ‘Yuka’, were found in Siberian permafrost. Here we recovered the less-damaged nucleus-like structures from the remains and visualised their dynamics in living mouse oocytes after nuclear transfer. Proteomic analyses demonstrated the presence of nuclear components in the remains. Nucleus-like structures found in the tissue homogenate were histone- and lamin-positive by immunostaining. In the reconstructed oocytes, the mammoth nuclei showed the spindle assembly, histone incorporation and partial nuclear formation; however, the full activation of nuclei for cleavage was not confirmed. DNA damage levels, which varied among the nuclei, were comparable to those of frozen-thawed mouse sperm and were reduced in some reconstructed oocytes. Our work provides a platform to evaluate the biological activities of nuclei in extinct animal species.