TBC1D4 and obesity due to melanocortin 4 receptor deficiency: Finally, in vitro expression of DNAJB3 protein caused a significant improvement in the insulin signaling pathway as shown by the increase in phosphorylation of IRS-1 (tyrosin), AKT and AS160, which eventually improved the glucose uptake in two different cell lines supporting the potential role of DNAJB3 in improving insulin signaling and glucose uptake in obesity and insulin resistance.