Rationale: Postmitotic cells, such as cardiomyocytes, seem to be particularly susceptible to proteotoxic stimuli, and large, proteinaceous deposits are characteristic of the desmin-related cardiomyopathies and crystallin cardiomyopathic diseases. Increased activity of protein clearance pathways in the cardiomyocyte, such as proteasomal degradation and autophagy, has proven to be beneficial in maintaining cellular and cardiac function in the face of multiple proteotoxic insults, holding open the possibility of targeting these processes for the development of effective therapeutics.

Objective: Here, we undertake an unbiased, total genome screen for RNA transcripts and their protein products that affect aggregate accumulations in the cardiomyocytes.

Methods and Results: Primary mouse cardiomyocytes that accumulate aggregates as a result of a mutant CryAB (αB-crystallin) causative for human desmin-related cardiomyopathy were used for a total genome-wide screen to identify gene products that affected aggregate formation. We infected cardiomyocytes using a short hairpin RNA lentivirus library in which the mouse genome was represented. The screen identified multiple candidates in many cell signaling pathways that were able to mediate significant decreases in aggregate levels.

Conclusions: Subsequent validation of one of these candidates, Jak1 (Janus kinase 1), a tyrosine kinase of the nonreceptor type, confirmed the usefulness of this approach in identifying previously unsuspected players in proteotoxic processes.

中文翻译：

---

无偏的高通量屏幕，以识别影响心肌细胞聚集水平的新颖效应子的新颖性和意义

原理：诸如心肌细胞之类的有丝分裂后细胞似乎特别容易受到蛋白毒性刺激的影响，而大量蛋白质沉积物是结蛋白相关性心肌病和晶状体心肌病的特征。事实证明，面对多种蛋白毒性损伤，增加心肌细胞中蛋白质清除途径的活性（例如蛋白酶体降解和自噬）有利于维持细胞和心脏功能，从而有可能针对这些过程开发有效的治疗方法。

目的：在这里，我们对RNA转录物及其蛋白产物进行了无偏见的全基因组筛选，这些转录物会影响心肌细胞中的聚集物积累。

方法和结果：将因人类结蛋白相关性心肌病的突变体CryAB（αB-crystallin）突变而积累聚集体的原代小鼠心肌细胞用于全基因组筛选，以鉴定影响聚集体形成的基因产物。我们使用代表小鼠基因组的短发夹RNA慢病毒文库感染了心肌细胞。该筛选在许多细胞信号传导途径中鉴定了多个候选者，这些候选者能够介导聚集体水平的显着降低。

结论：随后对这些候选基因之一Jak1（Janus激酶1）（一种非受体型酪氨酸激酶）的验证证实了该方法在鉴定蛋白毒性过程中未曾怀疑的参与者方面的有用性。