MiRNA Profile Associated with Replicative Senescence, Extended Cell Culture, and Ectopic Telomerase Expression in Human Foreskin Fibroblasts
MiRNA Profile Associated with Replicative Senescence, Extended Cell Culture, and Ectopic Telomerase Expression in Human Foreskin Fibroblasts
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DOI：
10.1371/journal.pone.0012519
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发表时间：
2010-09-01
期刊：
影响因子：
3.7
通讯作者：
Jarstfer, Michael B.
中科院分区：
文献类型：
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作者：
Bonifacio, Laura N.;Jarstfer, Michael B.
衰老是一个高度调节的过程，通过对各种刺激的反应而强制G1期阻滞来限制细胞复制。端粒DNA的破坏导致复制性衰老，端粒酶的表达可以抵消复制性衰老，从而导致许多人类细胞的永生化。关于人类细胞衰老过程中microRNA（miRNA）表达变化的数据有限，并且没有报道将端粒酶表达与衰老相关的miRNA的调节相关联。我们使用miRNA微阵列提供了一个详细的说明的miRNA档案的早期传代和衰老的人包皮（BJ）成纤维细胞，以及早期和晚期传代永生化成纤维细胞（BJ-hTERT），稳定表达人端粒酶逆转录酶亚基hTERT。测定在衰老中差异表达的所选miRNA在静止细胞中的表达，以鉴定与衰老相关的生长停滞特异性相关的miRNA。从这组衰老相关的miRNA中，我们证实了miR-143在年轻成纤维细胞中异位表达后诱导生长停滞的能力。值得注意的是，miR-143未能诱导BJ-hTERT细胞的生长停滞。重要的是，晚期传代永生化成纤维细胞与衰老野生型成纤维细胞的比较揭示了miR-146 a（一种在调节衰老相关分泌途径中具有经验证的作用的miRNA）也在延长的细胞培养期间独立于衰老而受到调节。发现miRNA表达受到异位hTERT表达的影响以及永生化成纤维细胞中的延长传代有助于全面理解端粒酶表达、衰老和细胞衰老过程之间的联系。
Senescence is a highly regulated process that limits cellular replication by enforcing a G1 arrest in response to various stimuli. Replicative senescence occurs in response to telomeric DNA erosion, and telomerase expression can offset replicative senescence leading to immortalization of many human cells. Limited data exists regarding changes of microRNA (miRNA) expression during senescence in human cells and no reports correlate telomerase expression with regulation of senescence-related miRNAs. We used miRNA microarrays to provide a detailed account of miRNA profiles for early passage and senescent human foreskin (BJ) fibroblasts as well as early and late passage immortalized fibroblasts (BJ-hTERT) that stably express the human telomerase reverse transcriptase subunit hTERT. Selected miRNAs that were differentially expressed in senescence were assayed for expression in quiescent cells to identify miRNAs that are specifically associated with senescence-associated growth arrest. From this group of senescence-associated miRNAs, we confirmed the ability of miR-143 to induce growth arrest after ectopic expression in young fibroblasts. Remarkably, miR-143 failed to induce growth arrest in BJ-hTERT cells. Importantly, the comparison of late passage immortalized fibroblasts to senescent wild type fibroblasts reveals that miR-146a, a miRNA with a validated role in regulating the senescence associated secretory pathway, is also regulated during extended cell culture independently of senescence. The discovery that miRNA expression is impacted by expression of ectopic hTERT as well as extended passaging in immortalized fibroblasts contributes to a comprehensive understanding of the connections between telomerase expression, senescence and processes of cellular aging.