Ploidy reductions in murine fusion-derived hepatocytes.
Ploidy reductions in murine fusion-derived hepatocytes.
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DOI：
10.1371/journal.pgen.1000385
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发表时间：
2009-02
期刊：
影响因子：
4.5
通讯作者：
Grompe, Markus
中科院分区：
文献类型：
--
作者：
Duncan, Andrew W.;Hickey, Raymond D.;Paulk, Nicole K.;Culberson, Andrew J.;Olson, Susan B.;Finegold, Milton J.;Grompe, Markus
我们先前表明，缺乏关键肝酶延胡索酰乙酰乙酸水解酶（FAH）的肝细胞与野生型血细胞之间的融合导致肝细胞重编程。FAH的表达恢复在杂交肝细胞，在体内扩增后，改善了FAH缺乏的影响。在这里，我们表明，融合衍生的多倍体肝细胞可以进行倍性减少，以产生子细胞的一半染色体内容。根据定义，融合杂种至少是四倍体。我们通过多种方法证明了二倍体染色体含量的减少。首先，融合衍生的肝细胞的细胞遗传学分析揭示了二倍体细胞的群体。其次，我们使用β-半乳糖苷酶和Y染色体证明标记分离。约2-5%的融合源性FAH阳性结节对一种或多种标志物呈阴性，与倍性减少期间的预期一致。接下来，使用报告系统，其中β-半乳糖苷酶只在融合衍生的肝细胞中表达，我们鉴定了表达β-半乳糖苷酶和FAH的二倍体细胞亚群。最后，我们跟踪标记分离，特别是在融合衍生的肝细胞与二倍体DNA含量。≥50%的Fah阳性细胞丢失半合子标志物。由于融合衍生的肝细胞是最低限度的四倍体，二倍体肝细胞的存在表明融合衍生的细胞可以经历倍性降低。此外，二倍体子细胞中标记物的高度丢失表明染色体/标记物以非随机方式丢失。因此，我们提出倍性减少导致产生遗传多样性的子细胞，其中核含量减少约50%。这种子细胞的产生增加了肝脏的多样性，这可能会增加肿瘤发生的可能性。肝脏包括许多不同类型的细胞，包括肝细胞。肝细胞执行许多生理功能，例如解毒、代谢和蛋白质合成。肝细胞具有与血细胞融合的能力，产生含有来自两种融合伴侣的细胞核的杂交肝细胞。在遗传性肝病的情况下，患病肝细胞和正常血细胞之间的融合可导致形成功能正常的杂交肝细胞。在这一系列的实验中，我们表明，融合肝细胞产生的子细胞中发现的亲本融合肝细胞中的DNA量的一半。此外，我们发现子细胞在遗传上彼此不同。肝脏内遗传多样性的增加可能导致肝细胞缺乏适当的生长控制，可能导致肿瘤形成和癌症。
We previously showed that fusion between hepatocytes lacking a crucial liver enzyme, fumarylacetoacetate hydrolase (FAH), and wild-type blood cells resulted in hepatocyte reprogramming. FAH expression was restored in hybrid hepatocytes and, upon in vivo expansion, ameliorated the effects of FAH deficiency. Here, we show that fusion-derived polyploid hepatocytes can undergo ploidy reductions to generate daughter cells with one-half chromosomal content. Fusion hybrids are, by definition, at least tetraploid. We demonstrate reduction to diploid chromosome content by multiple methods. First, cytogenetic analysis of fusion-derived hepatocytes reveals a population of diploid cells. Secondly, we demonstrate marker segregation using ß-galactosidase and the Y-chromosome. Approximately 2–5% of fusion-derived FAH-positive nodules were negative for one or more markers, as expected during ploidy reduction. Next, using a reporter system in which ß-galactosidase is expressed exclusively in fusion-derived hepatocytes, we identify a subpopulation of diploid cells expressing ß-galactosidase and FAH. Finally, we track marker segregation specifically in fusion-derived hepatocytes with diploid DNA content. Hemizygous markers were lost by ≥50% of Fah-positive cells. Since fusion-derived hepatocytes are minimally tetraploid, the existence of diploid hepatocytes demonstrates that fusion-derived cells can undergo ploidy reduction. Moreover, the high degree of marker loss in diploid daughter cells suggests that chromosomes/markers are lost in a non-random fashion. Thus, we propose that ploidy reductions lead to the generation of genetically diverse daughter cells with about 50% reduction in nuclear content. The generation of such daughter cells increases liver diversity, which may increase the likelihood of oncogenesis. The liver comprises many different types of cells, including hepatocytes. Hepatocytes perform numerous physiological functions, such as detoxification, metabolism, and protein synthesis. Hepatocytes have the ability to fuse with blood cells, generating hybrid hepatocytes that contain nuclei from both fusion partners. In cases of genetic liver disease, fusion between diseased hepatocytes and normal blood cells can result in the formation of hybrid hepatocytes that function normally. In this series of experiments, we show that fusion hepatocytes produce daughter cells with one-half the amount of DNA found in the parental fusion hepatocyte. Furthermore, we show that the daughter cells are genetically distinct from each other. The increase in genetic diversity within the liver could give rise to hepatocytes lacking proper growth control, potentially resulting in tumor formation and cancer.
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影响因子：
20.3
作者：
Holmgren, L;Szeles, A;Falk, KI
通讯作者：
Falk, KI
影响因子：
30.8
作者：
GROMPE, M;LINDSTEDT, S;FINEGOLD, M
通讯作者：
FINEGOLD, M
影响因子：
4
作者：
Piyamongkol, W;Bermúdez, MG;Wells, D
通讯作者：
Wells, D
DOI：
10.1073/pnas.101129998
发表时间：
2001-05-22
影响因子：
11.1
作者：
Bergsmedh, A;Szeles, A;Holmgren, L
通讯作者：
Holmgren, L
影响因子：
10.5
作者：
GROMPE, M;ALDHALIMY, M;SORIANO, P
通讯作者：
SORIANO, P