Early induction of the NGFI-B/Nur77 family genes in nephritis induced by anti-glomerular basement membrane antibody

We recently isolated a novel nuclear receptor NOR-1, which is a member of the steroid/thyroid receptor superfamily, and belongs to the NGFI-B/Nur77 family. In the present study, we examined gene expression of NOR-1 and its closely related members in nephritis induced by anti-glomerular basement membrane (GEM) antibody. The mRNA levels for NOR-1, NGFI-B and RNR-1 increased 24 h after injection of anti-GEM antibody (day 1). Gene expression of NOR-1 and NGFI-B reached maximum levels on day 3, gradually decreased thereafter and returned to control levels on day 28. RNR-1 reached a peak on day 7, and then decreased. Renal injuries were most prominent on day 7 and persisted until day 28, indicating that NOR-I, NGFI-B and RNR-1 genes are induced during the early stage of glomerulonephritis and may be associated with the progression of glomerulonephritis. The induction of the NGFI-B gene was less remarkable than that of NOR-1 and RNR-1. In addition, administration of glucocorticoid hormone suppressed NOR-1 and RNR-1 gene expression to almost normal levels, whereas NGFI-B gene expression was not significantly repressed. These findings also suggest that the NGFI-B/Nur77 family may possess different biological roles and NGFI-B might act as a general transcription factor in cell function.