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Enriched partial correlations in genome-wide gene expression profiles of hybrids (A. thaliana): a systems biological approach towards the molecular basis of heterosis


Heterosis is a well-known phenomenon but the underlying molecular mechanisms are not yet established. To contribute to the understanding of heterosis at the molecular level, we analyzed genome-wide gene expression profile data of Arabidopsis thaliana in a systems biological approach. We used partial correlations to estimate the global interaction structure of regulatory networks. Our hypothesis states that heterosis comes with an increased number of partial correlations which we interpret as increased numbers of regulatory interactions leading to enlarged adaptability of the hybrids. This hypothesis is true for mid-parent heterosis for our dataset of gene expression in two homozygous parental lines and their reciprocal crosses. For the case of best-parent heterosis just one hybrid is significant regarding our hypothesis based on a resampling analysis. Summarizing, both metabolome and gene expression level of our illustrative dataset support our proposal of a systems biological approach towards a molecular basis of heterosis.

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This work was supported by the German Research Council (DFG) under Grants RE 1654/2-1 and SE 611/3-1. We want to thank Dirk Hincha (MPIMP-Golm) and his lab for supporting our gene expression experiments.

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Correspondence to Dirk Repsilber.

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Contribution to the special issue “Heterosis in Plants”.

Communicated by F. van Eeuwijk.

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Andorf, S., Selbig, J., Altmann, T. et al. Enriched partial correlations in genome-wide gene expression profiles of hybrids (A. thaliana): a systems biological approach towards the molecular basis of heterosis. Theor Appl Genet 120, 249 (2010).

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  • Partial Correlation
  • Regulatory Interaction
  • Heterozygous Genotype
  • Shrinkage Estimator
  • Heterosis Effect