A mother and daughter centriole, attachedorthogonally
Centrioles are involved in the organization of themitotic spindle and in the completion ofcytokinesis.[19] Centrioles were previously thought to be required for the formation of a mitotic spindle in animal cells. However, more recent experiments have demonstrated that cells whose centrioles have been removed vialaser ablation can still progress through the G1 stage ofinterphase before centrioles can be synthesized later in a de novo fashion.[20] Additionally, mutant flies lacking centrioles develop normally, although the adult flies' cells lackflagella andcilia and as a result, they die shortly after birth.[21]The centrioles can self replicate during cell division.
Centrioles are a very important part ofcentrosomes, which are involved in organizingmicrotubules in thecytoplasm.[22][23] The position of the centriole determines the position of the nucleus and plays a crucial role in the spatial arrangement of the cell.
Sperm centrioles are important for 2 functions:[24] (1) to form the spermflagellum and sperm movement and (2) for the development of the embryo after fertilization. Thesperm supplies the centriole that creates the centrosome and microtubule system of the zygote.[25]
Inflagellates andciliates, the position of theflagellum orcilium is determined by the mother centriole, which becomes thebasal body. An inability of cells to use centrioles to make functional flagella and cilia has been linked to a number of genetic and developmental diseases. In particular, the inability of centrioles to properly migrate prior to ciliary assembly has recently been linked toMeckel–Gruber syndrome.[26]
Electron micrograph of a centriole from a mouse embryo.
Proper orientation of cilia via centriole positioning toward the posterior of embryonic node cells is critical for establishingleft-right asymmetry, during mammalian development.[27]
BeforeDNA replication, cells contain two centrioles, an oldermother centriole, and a youngerdaughter centriole. Duringcell division, a new centriole grows at the proximal end of both mother and daughter centrioles. After duplication, the two centriole pairs (the freshly assembled centriole is now a daughter centriole in each pair) will remain attached to each otherorthogonally untilmitosis. At that point the mother and daughter centrioles separate dependently on anenzyme calledseparase.[28]
The two centrioles in the centrosome are tied to one another. The mother centriole has radiating appendages at thedistal end of its long axis and is attached to its daughter at theproximal end. Each daughter cell formed after cell division will inherit one of these pairs. Centrioles start duplicating when DNA replicates.[19]
LECA, the last common ancestor of alleukaryotes was aciliated cell with centrioles.[citation needed] Some lineages of eukaryotes, such asland plants, do not have centrioles except in their motile male gametes. Centrioles are completely absent from all cells ofconifers andflowering plants, which do not have ciliate or flagellate gametes.[29]It is unclear if the last common ancestor had one[30] or two cilia.[31] Important genes such as those coding forcentrins, required for centriole growth, are only found in eukaryotes, and not inbacteria orarchaea.[30]
The wordcentriole (/ˈsɛntrioʊl/) usescombining forms ofcentri- and-ole, yielding "little central part", which describes a centriole's typical location near the center of the cell.
Typical centrioles are made of 9 triplets ofmicrotubules organized with radial symmetry.[32] Centrioles can vary the number of microtubules and can be made of 9 doublets of microtubules (as inDrosophila melanogaster) or 9 singlets of microtubules as inC. elegans. Atypical centrioles are centrioles that do not have microtubules, such as theProximal Centriole-Like found inD. melanogaster sperm,[33] or that have microtubules with no radial symmetry, such as in the distal centriole of humanspermatozoon.[34] Atypical centrioles may have evolved at least eight times independently during vertebrate evolution and may evolve in the sperm afterinternal fertilization evolves.[35]
It wasn't clear why the centriole became atypical until recently. The atypical distal centriole forms a dynamic basal complex (DBC) that, together with other structures in the sperm neck, facilitates a cascade of internal sliding that couples tail beating with head kinking. The atypical distal centriole's properties suggest that it evolved into a transmission system that couples the sperm tail motors to the whole sperm, thereby enhancing sperm function.[36]
^Leidel, S.; Delattre, M.; Cerutti, L.; Baumer, K.; Gönczy, P (2005). "SAS-6 defines a protein family required for centrosome duplication inC. elegans and in human cells".Nature Cell Biology.7 (2):115–25.doi:10.1038/ncb1220.PMID15665853.S2CID4634352.
^Rieder, C. L.; Faruki, S.; Khodjakov, A. (October 2001). "The centrosome in vertebrates: more than a microtubule-organizing center".Trends in Cell Biology.11 (10):413–419.doi:10.1016/S0962-8924(01)02085-2.ISSN0962-8924.PMID11567874.
^Flemming, W. (1875). Studien uber die Entwicklungsgeschichte der Najaden. Sitzungsgeber. Akad. Wiss. Wien 71, 81–147
^abcdeBloodgood RA. From central to rudimentary to primary: the history of an underappreciated organelle whose time has come. The primary cilium. Methods Cell Biol. 2009;94:3-52. doi: 10.1016/S0091-679X(08)94001-2. Epub 2009 Dec 23. PMID 20362083.
^Van Beneden, E. (1876). Contribution a l'histoire de la vesiculaire germinative et du premier noyau embryonnaire. Bull. Acad. R. Belg (2me series) 42, 35–97.
^Boveri, T. (1888). Zellen-Studien II. Die Befruchtung und Teilung des Eies von Ascaris megalocephala.Jena. Z. Naturwiss. 22, 685–882.
^Boveri, T.Ueber das Verhalten der Centrosomen bei der Befruchtung des Seeigel-Eies nebst allgemeinen Bemerkungen über Centrosomen und Verwandtes. Verh. d. Phys.-Med. Ges. zu Würzburg, N. F., Bd. XXIX, 1895.link.
^Boveri, T. (1901).Zellen-Studien: Uber die Natur der Centrosomen. IV. Fischer, Jena.link.
^Boveri, T. (1895). Ueber die Befruchtungs und Entwickelungsfahigkeit kernloser Seeigeleier und uber die Moglichkeit ihrer Bastardierung. Arch. Entwicklungsmech. Org. (Wilhelm Roux) 2, 394–443.
^Engelmann, T. W. (1880). Zur Anatomie und Physiologie der Flimmerzellen. Pflugers Arch. 23, 505–535.
^Vorobjev, I. A.; Nadezhdina, E. S. (1987).The Centrosome and Its Role in the Organization of Microtubules. International Review of Cytology. Vol. 106. pp. 227–293.doi:10.1016/S0074-7696(08)61714-3.ISBN978-0-12-364506-7.PMID3294718.. See also de Harven's own recollections of this work:de Harven, Etienne (1994). "Early observations of centrioles and mitotic spindle fibers by transmission electron microscopy".Biology of the Cell.80 (2–3):107–109.doi:10.1111/j.1768-322X.1994.tb00916.x.PMID8087058.S2CID84594630.
^Avidor-Reiss, T., Khire, A., Fishman, E. L., & Jo, K. H. (2015). Atypical centrioles during sexual reproduction. Frontiers in cell and developmental biology, 3, 21.Chicago
^Hewitson, Laura & Schatten, Gerald P. (2003)."The biology of fertilization in humans". In Patrizio, Pasquale; et al. (eds.).A color atlas for human assisted reproduction: laboratory and clinical insights. Lippincott Williams & Wilkins. p. 3.ISBN978-0-7817-3769-2. Retrieved9 November 2013.
^Turner, K., N. Solanki, H.O. Salouha, and T. Avidor-Reiss. 2022. Atypical Centriolar Composition Correlates with Internal Fertilization in Fish. Cells. 11:758,https://www.mdpi.com/2073-4409/11/5/758
^Khanal, S., M.R. Leung, A. Royfman, E.L. Fishman, B. Saltzman, H. Bloomfield-Gadelha, T. Zeev-Ben-Mordehai, and T. Avidor-Reiss. 2021. A dynamic basal complex modulates mammalian sperm movement. Nat Commun. 12:3808..https://doi.org/10.1038/s41467-021-24011-0
