Abstract
The ten-eleven translocation-1 (Tet1), which converts 5-methylcytosine (5mC) to 5-hydroxymethycytosine (5hmC), plays important roles in many important biological processes, such as mouse embryonic stem cells (ESCs) maintenance. However, the mechanisms for Tet-1 regulation remain largely unknown. Here we showed that miR-29 family (miR-29a, miR-29b and miR-29c) can directly repress Tet1 expression. We found that Tet1 was highly expressed and 5hmC was presented at relatively high levels in mouse ESCs, but the levels of both Tet1 and 5hmC were reduced during the early differentiation of ESCs. On the contrary, miR-29 level was increased in this process. ESCs stably transfecting with miR-29 precursors showed lower levels of Tet1 protein and 5hmC. Furthermore, we demonstrated that miR-29 overexpression selectively affected cell lineage markers and skewed ESC differentiation, which was similar in Tet1 knockdown ESCs. Our results indicate that miR-29 is a direct regulator of Tet1 in mouse ESCs.
Highlights
DNA methylation at the 5-position of cytosine (5-methylcytosine, 5mC) is essential for numerous biological processes, including gene regulation, genomic imprinting, X chromosome inactivation and mammalian development [1,2,3,4]
We found that ten-eleven translocation-1 (Tet1) was highly expressed in mouse embryonic stem cells (ESCs) and decreases during the early differentiation, and was partially regulated by miR-29
We performed dual luciferase reporter assay to identify which miRNAs are true regulator of Tet1 in vitro. miRNAs mimics or negative control (NC) mimics and a psiCheck2 luciferase reporter plasmid containing the whole length of Tet1 3′ untranslated region (3′UTR) were cotransfected into HEK-293T cells, and the luciferase activity were measured
Summary
DNA methylation at the 5-position of cytosine (5-methylcytosine, 5mC) is essential for numerous biological processes, including gene regulation, genomic imprinting, X chromosome inactivation and mammalian development [1,2,3,4]. Previous studies have demonstrated that this TET-catalyzed 5hmC regulates gene expression in differentiating colonocytes and colon cancers [10], and the levels of TET and 5hmC are dramatically reduced in human breast, liver, lung, pancreatic and prostate cancers [11]. Tet protein and 5hmC are present in high levels in mouse ESCs and adult brain, suggesting a role in epigenetic control of these cells and tissues [12,13,14,15]. Tet has an important role in mouse ESCs maintenance and functions to regulate the lineage differentiation potential of ESCs [16, 17]. Tet promotes 5mC hydroxylation, activates DNA demethylation, and is critical for neuronal activityregulated gene expression and memory formation [22,23,24]. Considering the important roles of Tet1/5hmC in regulation of many genes, it will be of a great need to elucidate how this catalytic process is controlled
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
