Downregulation of a Mitochondrial NAD+ Transporter (NDT2) Alters Seed Production and Germination in Arabidopsis.

Despite the fundamental importance of nicotinamide adenine dinucleotide (NAD+) for metabolism, the physiological roles of NAD+ carriers in plants remain unclear. We previously characterized the Arabidopsis thaliana gene (At1g25380), named AtNDT2, encoding a protein located in the mitochondrial inner membrane, which imports NAD+ from the cytosol using ADP and AMP as counter-exchange substrates for NAD+. Here, we further investigated the physiological roles of NDT2, by isolating a T-DNA insertion line, generating an antisense line and characterizing these genotypes in detail.

The mitochondrial NAD transporter (NDT1) plays important roles in cellular NAD homeostasis in Arabidopsis thaliana.

Nicotinamide adenine dinucleotide (NAD ) is an essential coenzyme required for all living organisms. In eukaryotic cells, the final step of NAD biosynthesis is exclusively cytosolic. Hence, NAD must be imported into organelles to support their metabolic functions.