- Endoreduplication
Endoreduplication is the duplication of the
genome withoutmitosis . Endoreduplication is a common process ineukaryote s and results in an increase in the nuclearDNA content, permitting amplification of thegenome of specialized cells. Moreover, the increase in theploidy level correlates with an increase in nuclear volume and cell size, suggesting that elevated nuclear DNA content is required to maintain larger cells. Inanimal s, endoreduplication is most frequent inAppendicularia , where endoreduplicated epithelial cells are used to produce feeding structures, and inarthropod s, where the highest value of the endopolyploidy occur in the Malpighian tubules and salivary glands of various dipters. Inmammal s, endopolyploidy is rare and evident only in thetrophoblast ,decidua andmyocardial cells. In contrast, endoreduplication is widespread inplant s, particularly inangiosperm s, and may occur in any cell types except the gametes, the meristematic and guard cells. The constant tissue-specific pattern of endopolyploidy in different organs suggest that endoreduplication cycles in plants constitute an essential part of the developmental programmes that are necessary for differentiation and for specialized function of given cells and tissues.References
External Links:
* [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10449413] Cebolla, A., J.M. Vinardell, E. Kiss, B. Olah, F. Roudier, A. Kondorosi and E. Kondorosi (1999) Themitotic inhibitor ccs52 is required for endoreduplication and ploidy-dependent cell enlargement in plants. Embo J. 18, 4476-4484.
* [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=search&DB=pubmed] Edgar, BA & Orr-Weaver, TL (2001) Endoreplication cell cycles: more for less. Cell. May 4;105(3):297-306
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