TP53 Inhibited AR Signaling Promote Enzalutamide Resistance in LNCaP cell

Background: To perform gene screening and search key knockout gene associated with enzalutamide resistance in LNCaP cells. Methods: Genome-scale CRISPR-Cas9 transfection were done to screen genes associated with enzalutamide resistance in LNCaP cells. Bioinformatic analysis of TP53 and AR expression correlated with prostate adenocarcinoma by using TCGA database. Knockout interfering RNA (shRNA) were synthesized in lentivirus and transfected into LNCaP cells by using Lipofectamine 3000. TP53 and AR detection was performed by using conventional molecular biology methods, such as western blot, RT-PCR and flow cytometer et al. Results: 27 high (NES<-1.7, P<0.01) and 26 low (NES>1.7, P<0.01) expressed genes were identified in enzalutamide resistance Cells. TP53 interacted with AR may play an important role in the development of enzalutamide resistance from PPI and RNA-seq data. Data from TCGA support that patient with TP53&AR low expression endured higher pathology stage, Gleason grades, more disease progress, recurrence, positive lymphnotes examination numbers and more abnormal bones scan results. LNCaP cell dealt with enzalutamide or with TP53 knockout showed inhibited cell cycle at G0~G1, increased apoptosis percentage and also inhibited cell proliferation. Conclusions: Current data support that TP53 protein inhabiting AR signaling promote enzalutamide resistance in LNCaP cell.

Knockout Gene-Based Evidence for PIWI-Interacting RNA Pathway in Mammals

The PIWI-interacting RNA (piRNA) pathway mainly consists of evolutionarily conserved protein factors. Intriguingly, many mutations of piRNA pathway factors lead to meiotic arrest during spermatogenesis. The majority of piRNA factor-knockout animals show arrested meiosis in spermatogenesis, and only a few show post-meiosis male germ cell arrest. It is still unclear whether the majority of piRNA factors expressed in spermatids are involved in long interspersed nuclear element-1 repression after meiosis, but future conditional knockout research is expected to resolve this. In addition, recent hamster knockout studies showed that a piRNA factor is necessary for oocytes—in complete contrast to the findings in mice. This species discrepancy allows researchers to reexamine the function of piRNA in female germ cells. This mini-review focuses on the current knowledge of protein factors derived from mammalian knockout studies and summarizes their roles in the biogenesis and function of piRNAs.

Glycine Betaine Transmethylase Mutant of Pseudomonas aeruginosa

ABSTRACT The gene for glycine betaine transmethylase (gbt) was identified in Pseudomonas aeruginosa strain Fildes III by biochemical, physiological, and molecular approaches. Based on sequence analysis, the knockout gene corresponded to an open reading frame (ORF) named PA3082 in the genome of P. aeruginosa PAO1. The translated product of this ORF displayed similarity to transferases of different microorganisms. Mutation in gbt blocked the utilization of choline and glycine betaine as carbon and nitrogen sources.