The Role Of TRIM28 Related Factors ZFP825 And ZFP825-like In Embryonic Stem Cells Differentiation

Krüppel-associated box domain zinc finger proteins(KRAB-ZFPs)are the largest family of transcriptional regulators in higher vertebrates.As a cofactor for members of the KRABZFPs transcription factor family,TRIM28 plays a role throughout development and is associated with chromatin condensation and gene suppression.KRAB-ZFPs can recruit TRIM28 through the KRAB domain,and then catalyze heterochromatin formation and transcriptional repression.Recently,the engagement of TRIM28 in distinct aspects of cellular biology has been extensively studied.TRIM28 is essential for development and differentiation.KRAB-ZFPs are also involved in many biological processes,including cell differentiation.However,the role and molecular mechanism of TRIM28 and its related KRAB-ZFPs in stem cell differentiation have not been clarified.In order to explore the mechanism of TRIM28 and its related factors in embryonic stem cell differentiation,we found a possible cofactor ZFP825 of TRIM28 by TRIM28 mass spectrometry analysis in mouse ES cells.Subsequently,we prepared an antibody that recognizes ZFP825/ZFP825-like,constructed the expression vectors of ZFP825 and ZFP825-like,and verified the interaction of TRIM28 with ZFP825 and ZFP825-like by co-immunoprecipitation experiments.In further functional study,we knocked down Zfp825/Zfp825-like with sh RNA in mouse ES cells.The result of RNA-seq suggested that the down-regulation of Zfp825/Zfp825-like significantly affected the normal development and differentiation.Subsequently,we performed a retinoic acid(RA)-induced embryoid body(EB)differentiation experiment and it was demonstrated that the down-regulation of Zfp825/Zfp825-like leads to defective differentiation of stem cells into neurons.To further distinguish the functions of ZFP825 and ZFP825-like,sh RNA specific to Zfp825 and Zfp825-like were constructed for subsequent experiments.Meanwhile,the result of Ch IP-seq showed that ZFP825/ZFP825-like and TRIM28 co-binding at retrotransposons in mouse ES cells,suggesting that they may regulate these TEs.However,the specific regulatory mechanism of TRIM28 related factor ZFP825/ZFP825-like affecting embryonic stem cell differentiation requires further research.