DPY30 knockdown suppresses colorectal carcinoma progression via inducing Raf1/MST2-mediated apoptosis.

Colorectal Carcinoma (CRC) is one of the most common malignant tumors of the digestive tract, with a high mortality rate. DPY30 is one of the core subunits of the histone methyltransferase complex, which was involved in many cancer processes. However, the role of DPY30 in the occurrence and progression of CRC remains unclear. In this study, we sought to evaluate the role and mechanism of DPY30 in CRC cells apoptosis. Here, we identified that knockdown of DPY30 significantly inhibited the HT29 and HCT116 cells proliferation in vitro. Moreover, the knockdown of DPY30 significantly increased the apoptosis rate and promoted the expression of apoptosis-related proteins in CRC cells. Meanwhile, DPY30 knockdown promoted CRC cells apoptosis through endogenous programmed death and in a caspase activation-dependent manner. Furthermore, RNA-seq analysis revealed that the action of DPY30 is closely related to the apoptosis biological processes, and screened its potential effectors Raf1. Mechanistically, DPY30 downregulation promotes MST2-induced apoptosis by inhibiting Raf1 transcriptional activity through histone H3 lysine 4 trimethylation (H3K4me3). In vivo experiments showed that DPY30 was correlated with Raf1 in nude mouse subcutaneous xenografts tissues significantly. Clinical colorectal specimens further confirmed that overexpression of DPY30 in malignant tissues was significantly correlated with Raf1 level. The vital role of the DPY30/Raf1/MST2 signaling axis in the cell death and survival rate of CRC cells was disclosed, which provides potential new targets for early diagnosis and clinical treatment of CRC.

Structural basis of Staphylococcus aureus Cas9 inhibition by AcrIIA14.

Bacteriophages have evolved a range of anti-CRISPR proteins (Acrs) to escape the adaptive immune system of prokaryotes, therefore Acrs can be used as switches to regulate gene editing. Herein, we report the crystal structure of a quaternary complex of AcrIIA14 bound SauCas9-sgRNA-dsDNA at 2.22 Å resolution, revealing the molecular basis for AcrIIA14 recognition and inhibition. Our structural and biochemical data analysis suggest that AcrIIA14 binds to a non-conserved region of SauCas9 HNH domain that is distinctly different from AcrIIC1 and AcrIIC3, with no significant effect on sgRNA or dsDNA binding. Further, our structural data shows that the allostery of the HNH domain close to the substrate DNA is sterically prevented by AcrIIA14 binding. In addition, the binding of AcrIIA14 triggers the conformational allostery of the HNH domain and the L1 linker within the SauCas9, driving them to make new interactions with the target-guide heteroduplex, enhancing the inhibitory ability of AcrIIA14. Our research both expands the current understanding of anti-CRISPRs and provides additional culues for the rational use of the CRISPR-Cas system in genome editing and gene regulation.

[Guiding role of three-column theory in manipulative reduction, small splint fixation and early rehabilitative exercises for Colles fracture].

OBJECTIVE: To explore guiding role of three-column theory in manipulative reduction, small splint fixation and early rehabilitative exercises of Colles fracture. METHODS: From August 2011 to February 2012,47 patients with Colles fractures were treated by manipulative reduction small splinting fixation and early rehabilitative exercises under the guidance of three-column theory, including 21 males and 26 females aged from 40 to 76 years old with an average of (65.5 +/- 2.3). According to AO fracture classification, 27 patients were type A (including 18 cases with type A2 and 9 cases with type A3) and 20 patients were type C (including 10 cases with type C1, 6 cases with type C2 and 4 cases with type C3). Pain and recovery time of swelling, postoperative complications were observed and recorded, Gartland-Werley scoring system were applied for evaluate functional recovery and biomechanical analysis of wrist joint at 12 weeks after operation. RESULTS: All patients were followed up for 3 to 9 months with average of 5 months. Pain relief time ranged from 5 to 15 d with average of (7.6 +/- 2.2) d,recovery time of swelling of opisthenar was for 6 to 13 d with an average of (8.9 +/- 1.9) d. Two patients occurred tension vesicle within 3 days after operation, but no other complications occurred. According to Gartland-Werley scoring system, 25 cases got excellent results, 18 cases good and 4 cases moderate at 12 weeks after operation. CONCLUSION: Under the guidance of three-column theory, treating Colles fracture by manipulative reduction, small splinting fixation and early rehabilitative exercises can reduce pain and swelling time, promote union of fracture, effectively rehabilitate wrist function, improve clinical efficacy, and fit for concept of biomechanics.