• Plants
• hypoxia
• dioxygenases
• P4Hs
• KDMs
• epigenetics

2-Oxoglutarate-dependent dioxygenases (2-OGDDs) are a superfamily of enzymes that require oxygen, reduced iron and 2-oxoglutarate (2-OG) to catalyse the oxidation of a substrate. 2-OGDDs are involved in several biological processes, including a wide range of post-translational modifications (PTMs), such as prolyl hydroxylation and lysine demethylation, recognising a large variety of substrates with different specificity. Histones are nuclear proteins that can be modified at their N-termininal.The Jumonji-C (JmjC) histone lysine demethylases (KDMs) are 2-OGD that remove methyl groups from N-methylated lysine residues on histone tails . KDMs are conserved across all eukaryotic kingdoms and the Arabidopsis thaliana genome encodes 21 KDMs that play important roles in many biological processes, such as flowering, germination and leaf senescence. Alongside, the present study is also focused on a subgroup of prolyl-4-hydroxylases (P4Hs) which belong also to the 2-OGDD family. These enzymes catalyse proline hydroxylation, an important PTM detected in a wide range of proteins, including plant secreted peptide hormones. Although the 2-OGDs require oxygen to catalyse the oxidation of a substrate - suggesting an oxygen-dependent activity - the roles of these enzymes in the hypoxic response has not been investigated in depth in plants so far.
In this study, I investigate the involvement of 2-OGDDs in the hypoxic response in higher plants by exploring the consequences of inactivation of single or multiple members in Arabidopsis of different 2-OGDs groups and by correlating their activity to the oxygen availability in plant tissues.