Determining cellular and biochemical function of a novel adhesion molecule in kidneys.
Acute kidney injury is an abrupt loss of kidney function that develops in short time with limited effective treatments other than kidney transplantation. We have identified TMIGD1 (Transmembrane immuno- globulin domain 1) as a novel receptor expressed in various organs and tissues, mainly in cell with epithelial origin. TMIGD1 regulates cell morphology and adhesion and its extracellular domain mediates its activity. Knocking down of TMIGD1 using short hairpin RNA (shRNA) increased cell death in human kidney epithelial cells (HK2). On the other hand, HEK293 cells over expressing TMIGD1 protected cells from oxidative stress and nutrient deprivation induced injuries. Furthermore, TMIGD1 expression is reduced in vivo and in vitro kidney injury models. TMIGD1 expression was regulated by ubiquitination and degradation by proteosome 26s. Thus, we present TMIGD1 as a novel receptor that plays important roles in regulation of cell morphology, cell- cell interaction and cell survival.