Rabbit Anti-Human DNAJB9 Polyclonal antibody

Fibrillary glomerulonephritis (FGN) is a rare disorder accounting for up to 1% of all glomerulonephritis (GN). FGN usually manifests as nephrotic or subnephrotic proteinuria, hematuria, and hypertension in patients after the sixth decade. The overall prognosis of FGN is very poor. Crescentic presentation of FGN is uncommon which may be diagnosed as rapidly progressive glomerulonephritis (RPGN) unless electron microscopy and/or special stains are done. We report a case of a young female who presented as RPGN but diagnosis was revised to crescentic FGN after electron microscopy and immunohistochemical staining with DNAJB9 stain. Patient remained dialysis-dependent after treatment with steroid and cyclophosphamide for 2 months and progressed to end-stage renal disease (ESRD). Crescentic FGN usually does not respond to treatment and invariably progresses to ESRD over few months. This case emphasizes the defining role of electron microscopy and special stains in diagnosing uncommon glomerular diseases.

DNAJB9 is known to be a member of the molecular chaperone gene family, whose cellular function has not yet been fully characterized. Here, we investigated the cellular function of DNAJB9 under strong mitogenic signals. We found that DNAJB9 inhibits p53-dependent oncogene-induced senescence (OIS) and induces neoplastic transformation under oncogenic RAS activation in mouse primary fibroblasts. In addition, we observed that DNAJB9 interacts physically with p53 under oncogenic RAS activation and that the p53-interacting region of DNAJB9 is critical for the inhibition of p53-dependent OIS and induction of neoplastic transformation by DNAJB9. These results suggest that DNAJB9 induces cell transformation under strong mitogenic signals, which is attributable to the inhibition of p53-dependent OIS by physical interactions with p53. This study might contribute to our understanding of the cellular function of DNAJB9 and the molecular basis of cell transformation.