An oxygen-sensing mechanism for angiosperm adaptation to altitude.

Flowering plants (angiosperms) can grow at extreme altitudes, and have been observed growing as high as 6,400 metres above sea level; however, the molecular mechanisms that enable plant adaptation specifically to altitude are unknown. One distinguishing feature of increasing altitude is a reduction in the partial pressure of oxygen (pO). Here we investigated the relationship between altitude and oxygen sensing in relation to chlorophyll biosynthesis-which requires molecular oxygen-and hypoxia-related gene expression.

Polyamine metabolism is altered in unpollinated parthenocarpic pat-2 tomato ovaries.

Facultative parthenocarpy induced by the recessive mutation pat-2 in tomato (Lycopersicon esculentum Mill.) depends on gibberellins (GAs) and is associated with changes in GA content in unpollinated ovaries. Polyamines (PAs) have also been proposed to play a role in early tomato fruit development.

Role of gibberellins in parthenocarpic fruit development induced by the genetic system pat-3/pat-4 in tomato.

The role of gibberellins (GAs) in the induction of parthenocarpic fruit-set and growth by the pat-3/pat-4 genetic system in tomato (Lycopersicon esculentum Mill.) was investigated using wild type (WT; Cuarenteno) and a near-isogenic line derived from the German line RP75/59 (the source of pat-3/pat-4 parthenocarpy). Unpollinated WT ovaries degenerated but GA3 application induced parthenocarpic fruit growth.