Phân tích sợi chromatin trong tế bào Hela bằng công nghệ điện tử chùm tia

Biophysics Reports - Tập 1 - Trang 51-60 - 2015
Xiaomin Li1,2, Hongli Feng1, Jianguo Zhang3, Lei Sun3, Ping Zhu1
1National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
2University of Chinese Academy of Sciences, Beijing, China
3Center for Biological Imaging, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China

Tóm tắt

Sự hiện diện và mô hình nếp gấp của chromatin trong tế bào eukaryote vẫn còn mơ hồ và gây tranh cãi. Trong nghiên cứu này, chúng tôi đã chuẩn bị các cắt lát siêu mỏng của tế bào Hela bằng ba phương pháp cố định và cắt khác nhau, tức là, cố định hóa học, đông lạnh áp suất cao với thay thế đông lạnh, và khối siêu vi sinh bằng SEM-FIB (chùm ion tập trung), và phân tích kiến trúc in vivo của sợi chromatin trong nhân tế bào Hela bằng công nghệ điện tử chùm tia. Kết quả cho thấy rằng sợi chromatin trong tế bào Hela eukaryote có khả năng được tổ chức theo một kiến trúc với đường kính khoảng 30 nm.

Từ khóa

#chromatin #tế bào Hela #công nghệ điện tử chùm tia

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