FGT-1 Knockdown Extends Life in Nematode Worms
Here is one example of ongoing explorations of the intersection between metabolism and longevity in lower animals. It is an open access paper, so you might take a look at the full PDF version:
Caenorhabditis elegans is widely used as a model for investigation of the relationships between aging, nutrient restriction and signalling via the DAF-2 receptor for insulin-like peptides and AGE-1 (PI 3-kinase) but the identity of the glucose transporters (GLUTs) that may link these processes is unknown. We unexpectedly find that of the eight putative GLUT-like genes only the two splice variants of one gene have a glucose transport function in an oocyte expression system. We have named this gene (fgt-1 (Facilitated Glucose Transporter, isoform 1).We show that knockdown of fgt-1 RNA leads to loss of glucose transport and reduced glucose metabolism in wild type worms. The FGT-1 glucose transporters of C. elegans thus play a key role in glucose energy supply to C. elegans. Importantly, knockdown of fgt-1 leads to an extension of lifespan equivalent, but not additive, to that observed in daf-2 and age-1 mutant worms. Our data are consistent with DAF-2 and AGE-1 signalling to glucose transport in C. elegans and this process being associated with the longevity phenotype in daf-2 and age-1 mutant worms. We propose that fgt-1 constitutes a common axis for the life-span extending effects of nutrient restriction and reduced insulin-like peptide signalling.