Hepatocyte nuclear factor 4 alpha is related to survival of the condensed mesenchyme in the developing mouse kidney

Hepatocyte nuclear factor 4 alpha (Hnf4α) is a transcription factor required for embryogenesis and organogenesis. In the adult kidney, Hnf4α is expressed at a high level in proximal tubules. Although its expression begins from the embryonic period, its function in the developing kidney has remained almost unknown. In this study, we investigated the role of Hnf4α in the cultured embryonic mouse kidney by gene silencing using the RNA interference method. Additionally, we identified the dynamics of Hnf4α in the microenvironment of the developing kidney. As a result of gene silencing, the cellular organization in the condensed mesenchyme (CM) fell into disorder and many apoptotic cells appeared. In addition, laser microdissection‐reverse transcriptase‐polymerase chain reaction provided evidence that Hnf4α gene expression began first in the CM. These results suggest the possibility that Hnf4α plays an important role in the regulation of the cell survival at the CM stage in nephrogenesis. Developmental Dynamics 239:1145–1154, 2010. © 2010 Wiley‐Liss, Inc.