InterPro domain: IPR044525

This entry represents a group of digalactosyldiacylglycerol synthases, including DGDG1 and DGDG2 from Arabidopsis. They are involved in the synthesis of the chloroplast lipid digalactosyldiacylglycerol (DGDG) [ 1 ]. DGDG provides stability to the photosystem I (PSI) complex, especially to the PsaA, PsaB, PsaC, PsaL and PsaH subunits [ 2 , 3 ]. The DGDG1 and DGDG2 homologues can also be found in soybean and Lotus. Besides in plastids, they are also expressed during later stages of nodule development in infected cells and in cortical tissue [ 4 ].

1. Disruption of the two digalactosyldiacylglycerol synthase genes DGD1 and DGD2 in Arabidopsis reveals the existence of an additional enzyme of galactolipid synthesis. Plant Cell 15, 2694-706
2. Decreased stability of photosystem I in dgd1 mutant of Arabidopsis thaliana. FEBS Lett 579, 3619-24
3. Digalactosyl-diacylglycerol deficiency impairs the capacity for photosynthetic intersystem electron transport and state transitions in Arabidopsis thaliana due to photosystem I acceptor-side limitations. Plant Cell Physiol 47, 1146-57
4. The galactolipid digalactosyldiacylglycerol accumulates in the peribacteroid membrane of nitrogen-fixing nodules of soybean and Lotus. J Biol Chem 279, 34624-30