Death domain-associated protein DAXX regulates noncoding RNA transcription at the centromere through the transcription regulator ZFAT

The centromere is an essential chromosomal structure for faithful chromosome segregation during cell division. No protein-coding genes exist at the centromeres, but centromeric DNA is actively transcribed into noncoding RNA (ncRNA). This centromeric transcription and its ncRNA products play important roles in centromere functions. We previously re-ported that the transcriptional regulator ZFAT (zinc -finger protein with AT hook) plays a pivotal role in ncRNA tran-scription at the centromere; however, it was unclear how ZFAT involvement was regulated. Here, we show that the death domain-associated protein (DAXX) promotes centromeric localization of ZFAT to regulate ncRNA transcription at the centromere. Coimmunoprecipitation analysis of endogenous proteins clearly reveals that DAXX interacts with ZFAT. In addition, we show that ectopic coexpression of ZFAT with DAXX increases the centromeric levels of both ZFAT and ncRNA, compared with ectopic expression of ZFAT alone. On the other hand, we found that siRNA-mediated depletion of DAXX decreases the centromeric levels of both ZFAT and ncRNA in cells ectopically expressing ZFAT. These results suggest that DAXX promotes the centromeric localization of ZFAT and ZFAT-regulated centromeric ncRNA transcription. Furthermore, we demonstrate that depletion of endogenous DAXX protein is sufficient to cause a decrease in the ncRNA levels at the centromeres of chromosomes 17 and X in which ZFAT regulates the transcription, indicating a physiological significance of DAXX in ZFAT-regulated centromeric ncRNA transcription. Taken together, these results demonstrate that DAXX regulates centromeric ncRNA transcription through ZFAT.

Automated summary

The centromere is a crucial chromosomal structure for accurate chromosome segregation during cell division. Centromeric DNA is transcribed into noncoding RNA (ncRNA), which plays important roles in centromere functions. This study reveals that the death domain-associated protein (DAXX) promotes the localization of ZFAT to the centromere and regulates ncRNA transcription. The results suggest that DAXX interacts with ZFAT and regulates centromeric ncRNA transcription, and the depletion of DAXX protein leads to a decrease in ncRNA levels at the centromere.