Homeosis

Homeosis

Homeosis is the transformation of one body part into another, arising from mutation in or misexpression of specific developmentally critical genes. It may be caused by mutations in Hox genes, found in animals, or others such as the MADS-box family in plants. Homeosis is a characteristic that has helped insects become as successful and diverse as they are.[1]

Homeotic mutations work by changing segment identity during development. For example, the Ultrabithorax genotype gives a phenotype wherein metathoracic and first abdominal segments become mesothoracic segments.[2] Another well-known example is Antennapedia: a gain-of-function allele causes legs to develop in the place of antennae.[3]

In botany, Rolf Sattler has revised the concept of homeosis (replacement) by his emphasis of partial homeosis in addition to complete homeosis, which is commonly accepted.[4]

Homeotic mutants in angiosperms are thought to be rare in the wild: in the annual plant Clarkia, (Onagraceae), homeotic mutants are known where the petals are replaced by a second whorl of sepal like organs, originating via a mutation governed by a single recessive gene.[5] The absence of lethal or deleterious consequences in floral mutants resulting in distinct morphological expressions has been a factor in the evolution of Clarkia, and perhaps also in many other plant groups.[6]

See also

References

  1. ^ Lodish et al., 2003. Molecular Cell Biology, 5th Edition. W.H. Freeman and Company, New York.[page needed]
  2. ^ Nüsslein-Volhard, Christiane; Wieschaus, Eric (1980). "Mutations affecting segment number and polarity in Drosophila". Nature 287 (5785): 795–801. doi:10.1038/287795a0. PMID 6776413. 
  3. ^ Schneuwly, Stephan; Klemenz, Roman; Gehring, Walter J. (1987). "Redesigning the body plan of Drosophilaby ectopic expression of the homoeotic gene Antennapedia". Nature 325 (6107): 816–818. doi:10.1038/325816a0. PMID 3821869. 
  4. ^ Sattler, R. (1988). "Homeosis in Plants". American Journal of Botany 75 (10): 1606–1617. doi:10.2307/2444710. JSTOR 2444710. 
  5. ^ Ford, V. S.; Gottlieb, L. D. (1992). "Bicalyx is a natural homeotic floral variant". Nature 358 (6388): 671–673. doi:10.1038/358671a0. 
  6. ^ Gottlieb, L. D. (1984). "Genetics and Morphological Evolution in Plants". The American Naturalist 123 (5): 681–709. doi:10.1086/284231. JSTOR 2461245. 



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  • homeosis — homeosis. См. гомеозис. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Homeosis — En biología del desarrollo, la homeosis es la transformación de una parte del cuerpo en otra como resultado de la mutación o de la alteración de la expresión de genes críticos en el desarrollo como los genes HOX. Los genes homeóticos reciben… …   Wikipedia Español

  • homeosis — homeozė statusas T sritis augalininkystė apibrėžtis Reiškinys, kuriam vykstant kuri nors organizmo dalis įgyja panašumo į kitą dalį. atitikmenys: angl. homeosis rus. гомеозис …   Žemės ūkio augalų selekcijos ir sėklininkystės terminų žodynas

  • homeosis mutation — homeozinė mutacija statusas T sritis augalininkystė apibrėžtis Mutacija, kurios metu vietoje vieno organo išsirutulioja kitas. atitikmenys: angl. homeosis mutation rus. гомеозистая мутация …   Žemės ūkio augalų selekcijos ir sėklininkystės terminų žodynas

  • homeosis — see homoeosis …   Dictionary of invertebrate zoology

  • homeosis — noun the formation of a normal plant or animal structure or organ in place of another at an abnormal site; the transformation of one body part to another …   Wiktionary

  • homeosis — Formation of a body part having characteristics normally found in a related or homologous part at another location in the body. [homeo + G. osis, condition] * * * ho·me·osis also ho·moe·osis .hō mē ō səs n a homeotic change or process in an… …   Medical dictionary

  • homeosis — [ˌhɒmɪ əʊsɪs] (also homoeosis) noun (plural homeoses si:z) Biology the replacement of part of one segment of an insect or other segmented animal by a structure characteristic of a different segment, especially through mutation. Derivatives… …   English new terms dictionary

  • homeosis — /hoʊmiˈoʊsəs/ (say hohmee ohsuhs) noun → homoeosis …  

  • homeosis — variant of homoeosis …   Useful english dictionary

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