Zfp68, also known as KRAZ1, is a Krüppel-associated box-containing zinc finger protein (KRAB-ZFP). KRAB-ZFPs play a role in transcriptional repression through interaction with the corepressor KAP-1, which is involved in heterochromatin-mediated gene silencing pathways [1,2]. This gene is important for understanding the mechanisms of gene regulation in cells.

Two studies have shown that KRAZ1 (Zfp68) binds to KAP-1, and this interaction is crucial for its transcriptional repression activity [2]. The centromeric targeting potential of KRAZ1 and KAP-1 is correlated with their silencing activities. A KRAB mutant of KRAZ1 that cannot bind KAP-1 loses its ability to localize to centromeric foci and repress transcription [1]. Also, overexpression of a VP16-KAP-1 fusion that binds KRAB but not HP1 leads to redistribution of KRAZ1 from centromeric foci and converts its silencing function into transcriptional activation [1].

In conclusion, Zfp68, through its interaction with KAP-1, is involved in the dynamic recruitment of target loci to centromeric heterochromatin for gene silencing in a histone deacetylase-dependent manner. These functional studies in the context of the Zfp68-KAP-1 interaction contribute to our understanding of gene regulation mechanisms, which may have implications for diseases related to abnormal gene silencing.

References:

1. Matsuda, E, Agata, Y, Sugai, M, Gonda, H, Shimizu, A. 2001. Targeting of Krüppel-associated box-containing zinc finger proteins to centromeric heterochromatin. Implication for the gene silencing mechanisms. In The Journal of biological chemistry, 276, 14222-9. doi:. https://pubmed.ncbi.nlm.nih.gov/11278721/

2. Agata, Y, Matsuda, E, Shimizu, A. . Two novel Krüppel-associated box-containing zinc-finger proteins, KRAZ1 and KRAZ2, repress transcription through functional interaction with the corepressor KAP-1 (TIF1beta/KRIP-1). In The Journal of biological chemistry, 274, 16412-22. doi:. https://pubmed.ncbi.nlm.nih.gov/10347202/