Molecular Biotechnology

, Volume 25, Issue 2, pp 149–184 | Cite as

Genomic imprinting and endosperm development in flowering plants

  • Rinke Vinkenoog
  • Catherine Bushell
  • Melissa Spielman
  • Sally Adams
  • Hugh G. Dickinson
  • Rod J. Scott
Review

Abstract

Genomic imprinting, the parent-of-origin-specific expression of genes, plays an important role in the seed development of flowering plants. As different sets of genes are imprinted and hence silenced in maternal and paternal gametophyte genomes, the contributions of the parental genomes to the offspring are not equal. Imbalance between paternally and maternally imprinted genes, for instance as a result of interploidy crosses, or in seeds in which imprinting has been manipulated, results in aberrant seed development. It is predominantly the endosperm, and not or to a far lesser extent the embryo, that is affected by such imbalance. Deviation from the normal 2m:1p ratio in the endosperm genome has a severe effect on endosperm development, and often leads to seed abortion. Molecular expression data for imprinted genes suggest that genomic imprinting takes place only in the endosperm of the developing seed. Although far from complete, a picture of how imprinting operates in flowering plants has begun to emerge. Imprinted genes on either the maternal or paternal side are marked and silenced in a process involving DNA methylation and chromatin condensation. In addition, on the maternal side, imprinted genes are most probably under control of the polycomb FIS genes.

Index Entries

Genomic imprinting epigenetics endosperm seed development apomixis FIS polycomb interploidy crosses interspecific hybridization 

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Copyright information

© Humana Press Inc. 2003

Authors and Affiliations

  • Rinke Vinkenoog
    • 1
  • Catherine Bushell
    • 1
  • Melissa Spielman
    • 1
  • Sally Adams
    • 1
    • 2
  • Hugh G. Dickinson
    • 3
  • Rod J. Scott
    • 1
  1. 1.Department of Biology and BiochemistryUniversity of BathBathUK
  2. 2.Friedrich Miescher InstitutBaselSwitzerland
  3. 3.Department of Plant SciencesUniversity of OxfordOxfordUK

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