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A basal body (synonymous with basal granule, kinetosome, and in older cytological literature with blepharoplast) is an organelle formed from a centriole, and a short cylindrical array of microtubules. It is found at the base of a eukaryotic undulipodium (cilium or flagellum) and serves as a nucleation site for the growth of the axoneme microtubules. Centrioles, from which basal bodies are derived, act as anchoring sites for proteins that in turn anchor microtubules within centrosomes, and are known as the microtubule organizing center (MTOC). These microtubules provide structure and facilitate movement of vesicles and organelles within many eukaryotic cells. The term, basal body is, however, reserved specifically for the base structures of eukaryote cilia and flagella which extend out from the cell. Basal bodies are derived from centrioles through a largely mysterious process. They are structurally the same, each containing a microtubule triplet 9 *3 helicoidal configuration forming a hollow cylinder. The overlying axoneme, however, consists of a 9 *2 + 2 structure. Regulation of basal body production and spatial orientation is a function of the nucleotide-binding domain of γ-tubulin.〔Y. Shang, C.-C. Tsao, and M. A. Gorovsky. 2005. Mutational analyses reveal a novel function of the nucleotide-binding domain of gamma-tubulin in the regulation of basal body biogenesis. ''J. Cell Biol.'' 171(6):1035-44. PMID 16344310 〕 Plants lack centrioles and only lower plants (such as mosses and ferns) with motile sperm have flagella and basal bodies. 〔 Philip E. Pack, Ph.D., Cliff's Notes: AP Biology 4th edition. 〕 ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「basal body」の詳細全文を読む スポンサード リンク
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