User:IsadoraofIbiza/Chloroplast/Sandbox


Chloroplast inheritance

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Like mitochondria, chloroplasts are usually inherited from a single parent. Biparental chloroplast inheritance—where plastid genes are inherited from both parent plants—occurs in very low levels in some flowering plants.[1]

Many mechanisms prevent biparental chloroplast DNA inheritance including selective destruction of chloroplasts or their genes within the gamete or zygote, and chloroplasts from one parent being excluded from the embryo. Chloroplasts may be sorted by origin among multiple offspring.[2]

Gymnosperms mostly pass on chloroplasts paternally, while flowering plants often inherit chloroplasts maternally. Flowering plants were once thought to only inherit chloroplasts maternally. However, there are now many documented cases of angiosperms inheriting chloroplasts paternally. [1]

Angiosperms which pass on chloroplasts maternally have many ways to prevent paternal inheritance. Most of them produce sperm cells which do not contain any plastids. There are many other documented mechanisms that prevent paternal inheritance in these flowering plants, such as different rates of chloroplast replication within the embryo.[1]

Among angiosperms, paternal chloroplast inheritance is observed more often in hybrids than in offspring from parents of the same species. This suggests that incompatible hybrid genes might interfere with the mechanisms that prevent paternal inheritance.[1]

References

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  1. ^ a b c d Hansen, A. Katie; Escobar, Linda K.; Gilbert, Lawrence E.; Jansen, Robert K. (1 January 2007). "Paternal, maternal, and biparental inheritance of the chloroplast genome in Passiflora (Passifloraceae): implications for phylogenetic studies". American Journal of Botany. 94 (1): 42–46. doi:10.3732/ajb.94.1.42. PMID 21642206. Retrieved 21 April 2013.
  2. ^ Birky Jr, C William (December 1995). "Uniparental inheritance of mitochondrial and chloroplast genes: Mechanisms and evolution" (PDF). Proceedings of the National Academy of Science. 92 (25): 11331–11338. doi:10.1073/pnas.92.25.11331. PMC 40394. PMID 8524780. Retrieved 21 April 2013.{{cite journal}}: CS1 maint: date and year (link)