Dicer is essential for formation of the heterochromatin structure in vertebrate cells

• Published in: Nature cell biology Vol. 6; no. 8; pp. 784 - 791
• Main Authors: Fukagawa, Tatsuo, Nogami, Masahiro, Yoshikawa, Mitsuko, Ikeno, Masashi, Okazaki, Tuneko, Takami, Yasunari, Nakayama, Tatsuo, Oshimura, Mitsuo
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.08.2004; Nature Publishing Group
• Subjects: Accumulation; Animals; Biomedical and Life Sciences; Blotting, Western; Cancer Research; Cell Biology; Cell Cycle Proteins - genetics; Cell Cycle Proteins - metabolism; Cell Death - genetics; Cell Line; Cell Survival; Cells; Centromere - chemistry; Chickens; Chromatin; Chromosomes, Human, Pair 21; Developmental Biology; Endoribonucleases - deficiency; Endoribonucleases - genetics; Endoribonucleases - physiology; Gene Silencing; Genetic aspects; Heterochromatin - chemistry; Heterochromatin - genetics; Heterochromatin - metabolism; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; letter; Life Sciences; Models, Biological; Mutation; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Phosphoproteins - genetics; Phosphoproteins - metabolism; Physiological aspects; Protein Kinases - genetics; Protein Kinases - metabolism; Protein-Serine-Threonine Kinases; Proteins; Restriction Mapping; RNA Interference; Stem Cells; Transgenes; Vertebrates; Japan
• DOI: 10.1038/ncb1155
• ISSN: 1465-7392; 1476-4679

RNA interference is an evolutionarily conserved gene-silencing pathway in which the nuclease Dicer cleaves double-stranded RNA into small interfering RNAs. The biological function of the RNAi-related pathway in vertebrate cells is not fully understood. Here, we report the generation of a conditional loss-of-function Dicer mutant in a chicken-human hybrid DT40 cell line that contains human chromosome 21. We show that loss of Dicer results in cell death with the accumulation of abnormal mitotic cells that show premature sister chromatid separation. Aberrant accumulation of transcripts from α-satellite sequences, which consist of human centromeric repeat DNAs, was detected in Dicer-deficient cells. Immunocytochemical analysis revealed abnormalities in the localization of two heterochromatin proteins, Rad21 cohesin protein and BubR1 checkpoint protein, but the localization of core kinetochore proteins such as centromere protein (CENP)-A and -C was normal. We conclude that Dicer-related RNA interference machinery is involved in the formation of the heterochromatin structure in higher vertebrate cells.