内核包膜蛋白Sun1的积累在进发性和变质性层状病变中具有病原性
Chia-Yen Chen1, Ya-Hui Chi, Rafidah Abdul Mutalif
1National Institute of Allergy and Infectious Diseases, The National Institutes of Health, Bethesda, MD 20892, USA.
Cell
|May 1, 2012
概括
LMNA基因的突变会导致肌肉发育不良和前列腺症等层状病变. 在小鼠模型和患者细胞中减少Sun1蛋白积累,意外地改善了健康和寿命,使Sun1与这些疾病有关.
科学领域:
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
背景情况:
- 人类LMNA基因突变导致细膜病变,包括Emery-Dreifuss肌肉发育不良 (AD-EDMD) 和Hutchinson-Gilford发育不良 (HGPS).
- Lmna null (Lmna(-/-))) 和LmnaΔ9突变小鼠作为AD-EDMD和HGPS的模型,表现出严重的病理和缩短寿命.
- 来自Lmna(-/-) 和LmnaΔ9小鼠的纤维细胞,类似于HGPS细胞,表现出特有的缺陷核.
研究的目的:
- 研究Sun1蛋白在LMNA相关疾病的发病过程中的作用.
- 为了确定是否针对Sun1积累可以改善疾病表型在拉米诺病的模型.
- 为了识别不同的LMNA基因突变诱导疾病背后的常见致病机制.
主要方法:
- 产生和分析Lmna(-/-) 和LmnaΔ9突变小鼠缺乏内部核膜蛋白 Sun1.1.
- 对转基因小鼠的组织病理和寿命的评估.
- 在LMNA突变纤维细胞和HGPS患者衍生细胞中评估核形态和细胞衰老,有和没有SUN1减少.
主要成果:
- 缺少Sun1的lmna(-/-) 或lmnaΔ9小鼠表现出显著减少的组织病理和增加的寿命.
- 减少LMNA突变纤维细胞和HGPS细胞中SUN1过度积累纠正了核缺陷.
- 在SUN1减少后,LMNA突变细胞和HGPS细胞的细胞衰老也得到改善.
结论:
- Sun1蛋白积累被确定为Lmna(-/-),LmnaΔ9和HGPS疾病的常见病原性因素.
- 准Sun1积累是对拉米诺病的潜在治疗策略.
- 这些发现凸显了Sun1在核膜完整性和LMNA相关条件下疾病进展中的关键作用.
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