FIGURE 6.

Isn1 accumulation is positively regulated by sodium and glucose. A, Western blot analysis shows that Isn1 protein accumulates with increasing provision of NA, but not with Nam. B, Isn1 protein accumulates with provision of NA in an npt1 mutant. C, Isn1 protein accumulates with provision of benzoic acid, an NA analog that is not converted to NAD⁺. D, Isn1 protein in SDC (3 μm NA) decreases with glucose restriction. E, restriction of glucose to 0.2% reduces accumulation of Isn1 upon provision of NA.