BioProject

Non-symbiotic hemoglobins are ubiquitously expressed proteins known to interact with nitric oxide, an inhibitor of mitochondrial respiration and an important signalling component. More...

Non-symbiotic hemoglobins are ubiquitously expressed proteins known to interact with nitric oxide, an inhibitor of mitochondrial respiration and an important signalling component. We evaluated the underlying molecular mechanisms of AtHb1 (also referred as AtGLB1 or AHb1) function, its effects on stress response and the interplay with nitric oxide. For this purpose, AtHb1 was overexpressed in Arabidopsis thaliana under control of the seed-specific promoter LeB4. We performed comparative transcriptome analysis of developing siliques from wild type (WT, Col-0) and transgenic plants subjected to control and moderate hypoxic conditions. The experimental design was used to analyze the underlying molecular mechanisms of AtHb1 function and to assess differences in the hypoxic response between WT and AtHb1-overexpressing seeds/siliques. Overall design: Hypoxic and control (normoxic) treatment was carried out with complete transgenic (T3) and WT plants 45 days after germination (DPG). Plants were aerated with a gas mixture containing 10.5% oxygen or ambient gas containing 21% oxygen for control samples in darkness. After one hour, plants were decapitated, immediately frozen in liquid nitrogen, and siliques were dissected in liquid nitrogen for RNA extraction and hybridization to Affymetrix microarrays. Hypoxic and control treatment runs with WT and AtHb1-overexpressing plants were repeated twice to provide 3 biological replicates (total number of samples = 12). Less...