Insulin Receptor Substrate 2 Expression and Involvement in Neuronal Insulin Resistance in Diabetic Neuropathy
Figure 1
IRS isoform expression in murine lumbar DRG. IRS isoforms were examined using RT-PCR ((a) and (b)) and Western blot ((c) and (d)). (a) RT-PCR was performed on adult C57Bl/6 mouse lumbar DRG ( mice) and comparisons were made among IRS1, IRS2, IRS3, and IRS4. GAPDH was used as the housekeeping gene. ΔCt values for IRS2 were significantly lower than any other isoform. (b) Analysis of IRS mRNA levels that were normalized to IRS1 mRNA levels revealed that IRS2 mRNA expression was 27-fold higher than IRS1 in the DRG. *denotes mice. ((c) and (d)) Representative Western blots of IRS1 and IRS2 protein in mouse lumbar DRG. Equal amounts of protein (20 μg) were loaded for each lane and samples were separated on 4–15% tris-glycine gel. Both IRS1 (c) and IRS2 (d) proteins were readily detectable. All mice were 8-week-old nondiabetic C57Bl/6 males.
