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Science:染色体“绝缘区域”的改变或将激活致癌基因的表达

2016-03-08 佚名 生物谷

图片来源:medicalxpress.com 近日,刊登在Science上的一项研究报告中,来自怀特黑德研究所的研究人员通过研究发现,名为“绝缘领域”(insulated neighborhoods)的环状染色体结构可以激活癌基因表达促进恶性肿瘤的生长。 研究者Richard Young表示,对癌基因错误调节的染色体结构角色的理解或可帮助深入探索其对机体基因组结构的影响,从而为改善人类健康

图片来源:medicalxpress.com

近日,刊登在Science上的一项研究报告中,来自怀特黑德研究所的研究人员通过研究发现,名为“绝缘领域”(insulated neighborhoods)的环状染色体结构可以激活癌基因表达促进恶性肿瘤的生长。

研究者Richard Young表示,对癌基因错误调节的染色体结构角色的理解或可帮助深入探索其对机体基因组结构的影响,从而为改善人类健康和疾病进展提供帮助。此前研究者对人类基因组结构进行了绘图并且描述了健康细胞中基因组结构对基因控制的影响,通过绘制基因组的3D构象图谱,研究者就在染色体绝缘区域中发现了控制细胞身份的关键基因,绝缘区域中的环状结构可以通过锚定位点被蛋白质CTCF所维持,而所有必要的基因调节,包括合适的激活或抑制性控制都是在这些附带的绝缘区域中发生的。

同时研究者还发现,这些CTCG锚定位点在人类机体的多种不同细胞中都处于被维护的状态,而且其在灵长类动物的基因组中还是高度保守的,这就强调了其对正常发育的重要性,一些广泛的结构保守性就可以帮助科学家们推测基因组构象的破坏和疾病,比如癌症之间的关联。随后研究者对50多种癌症类型进行系统性的基因组分析揭示了影响CTCF锚定位点的基因突变,这些突变会引发绝缘区域界限的缺失,比如研究者在T细胞急性淋巴母细胞白血病、食道癌及肝癌中发现的绝缘区域的破坏。

Young说道,我们并不知道是否这些类型的突变会引发癌症,如今我们有多种实例来解释这些干扰打断如何驱动致癌的发生。致癌机制并不仅仅存在于癌症中,其对于科学家们鉴别驱动癌症的基因也至关重要。在某些癌症中,比如食管癌中,CTCF位点发生的最频繁的遗传突变或许是相当惊人的;此外研究者表示,他们已经利用基因编辑的技术将CTCF锚定位点的剔除引入到非恶性的细胞中,这些突变将足以激活正常细胞中存在的癌基因的表达。

这项最新研究阐明了单一癌症患者机体的基因组的图谱结构,对于改善癌症的诊断及治疗步骤将非常重要,如今科学家们将去深入研究理解基因组结构中的微小干扰如何引发机体癌变,后期他们或许可以开发出新型的策略来有效诊断并且修复染色体绝缘区域的错误。

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    2016-03-10 jambiya
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    2016-03-10 jichang
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