Hydration-dependent gene expression in Brassica oleracea anthers

Abstract 

Anther physiology is characterized by developmentally controlled dehydration. Screening of an anther cDNA expression library with an antiserum raised against proteins isolated from the surface of Brassica oleracea pollen grains resulted in the isolation of bopc15 and bopc34, sequences similar to water stress-inducible genes. Bopc15 transcripts were exclusively present in pollen. The mRNA of bopc34 was found in various tissues, but not in pollen. The accumulation of both transcripts preceded anther dehydration. Premature anther dehydration induced by imposed drought stress affects gene expression in both the sporophytic and gametophytic portions of the anthers the levels of bopc15 and bopc34 transcripts increased to an extent dependent on developmental stage and duration of treatment. The inducible bopc15 transcript accumulation was reversible by rehydration. Bopc34 transcript levels, on the other hand, do not follow this pattern.