Dynamic changes in DNA demethylation in the tree shrew ( Tupaia belangeri chinensis) brain during postnatal development and aging

Zool Res. 2017 Mar 18;38(2):96-102. doi: 10.24272/j.issn.2095-8137.2017.013.

Abstract

Brain development and aging are associated with alterations in multiple epigenetic systems, including DNA methylation and demethylation patterns. Here, we observed that the levels of the 5-hydroxymethylcytosine (5hmC) ten-eleven translocation (TET) enzyme-mediated active DNA demethylation products were dynamically changed and involved in postnatal brain development and aging in tree shrews (Tupaia belangeri chinensis). The levels of 5hmC in multiple anatomic structures showed a gradual increase throughout postnatal development, whereas a significant decrease in 5hmC was found in several brain regions in aged tree shrews, including in the prefrontal cortex and hippocampus, but not the cerebellum. Active changes in Tet mRNA levels indicated that TET2 and TET3 predominantly contributed to the changes in 5hmC levels. Our findings provide new insight into the dynamic changes in 5hmC levels in tree shrew brains during postnatal development and aging processes.

Keywords: 5-hydroxymethylcytosine; Brain development and aging; DNA demethylation; Tree shrew.

MeSH terms

  • Aging / physiology*
  • Animals
  • Brain / metabolism*
  • DNA Demethylation*
  • Epigenesis, Genetic
  • Gene Expression Regulation, Developmental / physiology
  • Tupaiidae / metabolism*

Grant support

This work was supported by the Hundred-Talent Program of Chinese Academy of Sciences (Y406541141; 1100050210) to J.L., the National Natural Science Foundation of China (81471313; 91649119) to J.L., the National Science and Technology Infrastructure Program (2014BAI01B01-04) to S.L., and the National Natural Science Foundation of China (31260242 to) F.L