Transient introduction of human telomerase mRNA improves hallmarks of progeria cells
Transient introduction of human telomerase mRNA improves hallmarks of progeria cells
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DOI：
10.1111/acel.12979
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发表时间：
2019-08-01
期刊：
影响因子：
7.8
通讯作者：
Shay, Jerry W.
中科院分区：
文献类型：
--
作者：
Li, Yanhui;Zhou, Gang;Shay, Jerry W.
哈钦森-吉尔福德早衰综合征（HGPS）的特点是由于LMNA基因的新生突变而加速衰老。这种突变会产生一种异常的层状蛋白A，称为progerin，这种蛋白缺乏去除法酰化结构域所需的剪接位点。随后，早衰蛋白在核膜中积累，破坏核结构、染色质组织和基因表达。这些改变通常与快速端粒侵蚀和细胞老化有关。在这里，我们进一步表征了HGPS细胞中的细胞和分子异常，并报告了通过引入体外转录和纯化的人类端粒酶（hTERT） mRNA，一些异常的显著逆转。端粒相关蛋白DNA PKcs/Ku70/Ku80的表达存在个体内异质性，低表达的细胞端粒较短。此外，早衰症中异染色质标记物H3K9me3的缺失与端粒侵蚀加速有关。在端粒较短的HGPS细胞系中，瞬时转染hTERT mRNA可增加端粒长度，增加端粒相关蛋白的表达，增加增殖能力和细胞寿命，并通过β -半乳糖苷酶的表达和炎症细胞因子的分泌来逆转细胞衰老的表现。出乎意料的是，mRNA hTERT也改善了核形态。与法尼基转移酶抑制剂（FTI） lonafarnib联合，hTERT mRNA促进HGPS细胞增殖。我们的研究结果表明，人类端粒酶的瞬时表达与FTIs联合可能代表了HGPS的一种改进的治疗方法。
Hutchinson-Gilford progeria syndrome (HGPS) is characterized by accelerated senescence due to a de novo mutation in the LMNA gene. The mutation produces an abnormal lamin A protein called progerin that lacks the splice site necessary to remove a farnesylated domain. Subsequently, progerin accumulates in the nuclear envelope, disrupting nuclear architecture, chromatin organization, and gene expression. These alterations are often associated with rapid telomere erosion and cellular aging. Here, we further characterize the cellular and molecular abnormalities in HGPS cells and report a significant reversal of some of these abnormalities by introduction of in vitro transcribed and purified human telomerase (hTERT) mRNA. There is intra-individual heterogeneity of expression of telomere-associated proteins DNA PKcs/Ku70/Ku80, with low-expressing cells having shorter telomeres. In addition, the loss of the heterochromatin marker H3K9me3 in progeria is associated with accelerated telomere erosion. In HGPS cell lines characterized by short telomeres, transient transfections with hTERT mRNA increase telomere length, increase expression of telomere-associated proteins, increase proliferative capacity and cellular lifespan, and reverse manifestations of cellular senescence as assessed by beta-galactosidase expression and secretion of inflammatory cytokines. Unexpectedly, mRNA hTERT also improves nuclear morphology. In combination with the farnesyltransferase inhibitor (FTI) lonafarnib, hTERT mRNA promotes HGPS cell proliferation. Our findings demonstrate transient expression of human telomerase in combination with FTIs could represent an improved therapeutic approach for HGPS.