Laboratory of Molecular and Cellular Biology, LIM 15, Department of Neurology, Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, Brazil.
Vascular Biology Laboratory, Faculdade de Medicina FMUSP, Heart Institute (InCor), Hospital das Clinicas HCFMUSP, Universidade de Sao Paulo, Sao Paulo, Brazil.
DNA Cell Biol. 2019 Sep;38(9):955-961. doi: 10.1089/dna.2019.4752. Epub 2019 Jul 30.
The chromatin-remodeling complex ATRX/DAXX is one of the major epigenetic factors that controls heterochromatin maintenance due to its role in histone deposition. ATRX is involved in nucleosome configuration and maintenance of higher order chromatin structure, and DAXX is a specific histone chaperone for H3.3 deposition. Dysfunctions in this complex have been associated with telomere shortening, which influences cell senescence. However, data about this complex in brain tissue related to aging are still scarce. Therefore, in the present study, we analyzed ATRX and DAXX expressions in autopsied human brain specimens and the telomere length. A significant decrease in gene and protein expressions was observed in the brain tissues from the elderly compared with those from the young, which were related to short telomeres. These findings may motivate further functional analysis to confirm the ATRX-DAXX complex involvement in telomere maintenance and brain aging.
染色质重塑复合物 ATRX/DAXX 是主要的表观遗传因子之一，由于其在组蛋白沉积中的作用，可控制异染色质的维持。ATRX 参与核小体构象和高级染色质结构的维持，而 DAXX 是 H3.3 沉积的特定组蛋白伴侣。该复合物的功能障碍与端粒缩短有关，这会影响细胞衰老。然而，与衰老相关的脑组织中关于该复合物的数据仍然很少。因此，在本研究中，我们分析了尸检人脑标本中 ATRX 和 DAXX 的表达以及端粒长度。与年轻人相比，老年人脑组织中的基因和蛋白表达显著下降，这与端粒较短有关。这些发现可能会激励进一步的功能分析，以确认 ATRX-DAXX 复合物在端粒维持和大脑衰老中的作用。
