https://www.selleckchem.com/products/jph203.html Ulcerative colitis (UC) is a chronic inflammatory bowel disease, characterized by relapsing and remitting colon mucosal inflammation. For patients suffering from UC, a higher risk of colon cancer has been widely recognized. Here, we found that Elf4-/- mice developed colon tumors with 3 cycles of dextran sulfate sodium salt (DSS) treatment alone. We further showed that ELF4 suppression was prevalent in both patients with UC and DSS-induced mice models, and this suppression was caused by promoter region methylation. ELF4, upon PARylation by PARP1, transcriptionally regulated multiple DNA damage repair machinery components. Consistently, ELF4 deficiency leads to more severe DNA damage both in vitro and in vivo. Oral administration of montmorillonite powder can prevent the reduction of ELF4 in DSS-induced colitis models and lower the risk of colon tumor development during azoxymethane (AOM) and DSS induced colitis-associated cancer (CAC). These data provided additional mechanism of CAC initiation and supported the "epigenetic priming model of tumor initiation".Methanol biotransformation can expand biorefinery substrate spectrum other than biomass by using methylotrophic microbes. Ogataea (Hansenula) polymorpha, a representative methylotrophic yeast, attracts much attention due to its thermotolerance, but the low homologous recombination (HR) efficiency hinders its precise genetic manipulation during cell factory construction. Here, recombination machinery engineering (rME) is explored for enhancing HR activity together with establishing an efficient CRISPR-Cas9 system in O. polymorpha. Overexpression of HR-related proteins and down-regulation of non-homologous end joining (NHEJ) increased HR rates from 20%-30% to 60%-70%. With these recombination perturbation mutants, a competition between HR and NHEJ is observed. This HR up-regulated system has been applied for homologous integration of large fragments and in vivo assemb