Table I.

Overrepresentation of stress-responsive genes in OGs that expanded in the Arabidopsis lineage and the major contributing duplication mechanisms

Statistical TestUp-RegulationDown-Regulation
A-MA-RA-PA-MA-RA-P
ExpaT/NbExpT/NExpT/NExpT/NExpT/NExpT/N
Abiotic stress conditionsc
    UV-B+T+T+T+N
    Wounding+T++++
    Drought++T+++
    Cold4C+N+N+N
    Heat+N+N
    Salt+++
    Osmotic+++
Biotic stress conditionsc
    Flg22+T+T+++
    GST-NPP1+T+T+T
    HrcC-+T+T+T
    P. infestans+T+T+T
    Psph+T+T+T
    HrpZ+++
    AvrRpm1+++
    DC3000+++
  • a A + sign indicates that the ratio of stress-responsive genes in expanded OGs versus nonexpanded OGs is significantly higher (P ≤ 0.05) than for nonresponsive genes.

  • b T/N, Tandem versus nontandem; T, the genes responsive for a given stress condition are significantly enriched in tandem relative to nontandem genes; N, significant enrichment of nontandem genes (q < 0.05).

  • c Condition names follow those from AtGenExpress.