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[[Image:Eukarya Flagella.svg|thumb|right|Schematic of the eukaryotic flagellum. 1-axoneme, 2-cell membrane, 3-IFT (Intraflagellar Transport), 4-Basal body, 5-Cross section of flagellum, 6-Triplets of microtubules of basal body.]]
[[Image:Eukarya Flagella.svg|thumb|right|Schematic of the eukaryotic flagellum. 1-axoneme, 2-cell membrane, 3-IFT (Intraflagellar Transport), 4-Basal body, 5-Cross section of flagellum, 6-Triplets of microtubules of basal body.]]
[[Image:Chlamydomonas TEM 09.jpg|thumb|right|Longitudinal section through the flagella area in ''[[Chlamydomonas reinhardtii]]''. In the cell apex is the basal body that is the anchoring site for a flagellum. Basal bodies originate from and have a substructure similar to that of centrioles, with nine peripheral microtubule triplets (see structure at bottom center of image).]]
[[Image:Chlamydomonas TEM 09.jpg|thumb|right|Longitudinal section through the flagella area in ''[[Chlamydomonas reinhardtii]]''. In the cell apex is the basal body that is the anchoring site for a flagellum. Basal bodies originate from and have a substructure similar to that of centrioles, with nine peripheral microtubule triplets (see structure at bottom center of image).]]
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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.
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.

The basal granule is a modified centriole. It is present in the ectoplasm. The tubules are of each triplet are designed as A,B,C from the center to the periphery. Both A,B cross the basal plate and continue as peripheral doublet above the pellicle in the axoneme. However , the tubule C terminates at the basal plate . Thus the triplets of the basal granule are converted into the flagellar or the cillary doublets there are no central microtubules in the basal granule. The basal granule is also connected to the plasma membrane and the nucleus by communication tubules called the rootlets the rootlets can pull the flagellum and alter its orientation .
Regulation of basal body production and spatial orientation is a function of the nucleotide-binding [[Protein domain|domain]] of [[γ-tubulin]].<ref>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 </ref>
Regulation of basal body production and spatial orientation is a function of the nucleotide-binding [[Protein domain|domain]] of [[γ-tubulin]].<ref>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 </ref>



Revision as of 06:33, 9 October 2015

Schematic of the eukaryotic flagellum. 1-axoneme, 2-cell membrane, 3-IFT (Intraflagellar Transport), 4-Basal body, 5-Cross section of flagellum, 6-Triplets of microtubules of basal body.
Longitudinal section through the flagella area in Chlamydomonas reinhardtii. In the cell apex is the basal body that is the anchoring site for a flagellum. Basal bodies originate from and have a substructure similar to that of centrioles, with nine peripheral microtubule triplets (see structure at bottom center of image).

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.[1]

Plants lack centrioles and only lower plants (such as mosses and ferns) with motile sperm have flagella and basal bodies. [2]

References

  1. ^ 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
  2. ^ Philip E. Pack, Ph.D., Cliff's Notes: AP Biology 4th edition.
  • Histology image: 21804loa – Histology Learning System at Boston University - "Ultrastructure of the Cell: ciliated epithelium, cilia and basal bodies"