Protein liquid-liquid phase separation (LLPS), a pivotal phenomenon intricately linked to cellular processes, is regulated by various other proteins. However, there is still a lack of high-throughput methods for screening protein regulators of LLPS in target proteins. Here, we developed a CRISPR/Cas9-based screening method to identify protein phase separation regulators by integrating bimolecular fluorescence complementation (BiFC) and fluorescence-activated cell sorting (FACS). Using this newly developed method, we screened the RNA-binding proteins that regulate PABPN1 phase separation and identified the tumor suppressor QKI as a promoter of PABPN1 phase separation. Furthermore, QKI exhibits decreased expression levels and diminished nuclear localization in colorectal cancer cells, resulting in reduced PABPN1 phase separation, which, in turn, promotes alternative polyadenylation (APA), cell proliferation, and migration in colorectal cancer.
Humans ; Colorectal Neoplasms/genetics* ; RNA-Binding Proteins/genetics* ; Poly(A)-Binding Protein I/genetics* ; CRISPR-Cas Systems ; Flow Cytometry ; Cell Proliferation ; Cell Line, Tumor ; Cell Movement

Objective To explore the application value of chest dual-energy subtraction (DES) technology in the diagnosis of occupational pneumoconiosis. Methods A total of 86 patients with suspected pneumoconiosis and 21 dust-exposure workers were selected as the research subjects using random sampling method. The posterior and anterior chest radiographs were taken by digital radiography (DR) and DES technology, and the difference of chest radiographs of DR, DES and combined groups were compared. Results The positive rate of superior chest radiographs in DR group was higher than that in DES group (72.9% vs 56.1%, P<0.05). The determination of shadow shape and size, total density and stage of pneumoconiosis on chest radiographs in DES group and combined group were consistent with those in DR group (all Kappa values >0.75, all P<0.01). However, the judgment of small shadow intensity, small shadow aggregation and large shadow distribution in the two groups were not superior to those in the DR group (Kappa value was 0.67, 0.74, both P<0.01). There was no significant difference between DES group and DR group in the determination of small shadow intensity, small shadow aggregation and large shadow distribution (P>0.05). However, there were statistically significant difference in this index between the combined group and DES group and DR group (all P<0.01). There was no statistically significant difference in shadow shape and size, total density and stage of pneumoconiosis in chest radiographs among these three groups (all P>0.05). Conclusion There was no difference between DES alone and DES combined with DR for the diagnosis of pneumoconiosis in terms of shadow shape and size, total density and stage of pneumoconiosis when compared with the gold standard DR. The value of DES in the diagnosis of pneumoconiosis needs further study.