Mex3c mutation affects lactation through impairing milk ejection in female mice.

Mouse Mex3c encodes RNA-binding proteins of variant length through alternative splicing. Its mutation results in multiple defects including growth retardation, perturbed energy balance, and defective antiviral innate immunity. Here we report that Mex3c mutation affects mammary gland development and lactation in female mice. Pups of Mex3c mutant dams die of starvation soon after birth. Milk contents are present in the alveoli but deficient in the ducts of the mammary glands in mutant mice. Mutant mice do not show prolactin or oxytocin deficiency. They also develop myoepithelial cells in the mammary glands. Mex3c is expressed in the mammary gland epithelium. Our data suggest that functional defects in mammary gland epithelium or myoepithelial cells could cause lactation defects.

Construction of a Mex3c Gene-Deficient Mouse Model to Study C-FOS Expression in Hypothalamic Nuclei and Observe Morphological Differences in Embryonic Neural Tube Development.

BACKGROUND This study utilized CRISPR/Cas9 gene editing technology to construct a Mex3c gene-deficient mouse model, and studied C-FOS expression in hypothalamic nuclei. MATERIAL AND METHODS Thirty Mex3c-/+ mice, 30 mice in the normal group, and 30 Mex3c-/+ mice were randomly divided into control, leptin, and ghrelin groups according to different intraperitoneal injections. HE and Nissl staining were performed to observe the morphology of hypothalamic nerve cells. The C-FOS expression in hypothalamic nuclei of each group was analyzed by immunohistochemical techniques. HE staining was used to observe neural tube morphology, and LFB staining was used to observe nerve myelin sheath morphology. TEM was used to observe neuronal ultrastructure and immunohistochemical techniques were utilized to analyze nestin expression. RESULTS C-FOS expression was lower in the normal control group than in the leptin and ghrelin groups. The Mex3c control group and the leptin group had higher C-FOS expression than the ghrelin group. In neural tube studies, no significant differences were found in the neural tube pathological sections of E14.5-day embryos in each group. Nestin results demonstrated lower expression in the normal group and there was little difference between the HD and Mex3c groups. CONCLUSIONS Mex3c appears to participate in the regulation of energy metabolism by inducing C-FOS expression in the hypothalamus. The neural tubes of the offspring of Mex3c-/+ mice had defects during development.

miR-26b-5p Inhibits the Proliferation, Migration and Invasion of Human Papillary Thyroid Cancer in a ß-Catenin-Dependent Manner.

BACKGROUND: miR-26b-5p is reported to be involved in the progression of multiple cancers, but its function and mechanism in human papillary thyroid cancer (PTC) remain unknown. We aimed to uncover the function and mechanism of miR-26b-5p in PTC. METHODS: We performed qRT-PCR to detect the differences in miR-26b-5p expression between normal tissue and PTC. In vitro, we established cell lines stably overexpressing miR-26b-5p and investigated the function and underlying mechanism of miR-26b-5p in PTC. RESULTS: miR-26b-5p was downregulated in PTC compared with normal tissue. miR-26b-5p was correlated with the clinical stage. miR-26b-5p inhibited the proliferation, invasion and migration of PTC cell lines. We next detected EMT and proliferation markers. miR-26b-5p was shown to exert its function in a ß-catenin-dependent manner. CONCLUSION: Taken together, our results showed that miR-26b-5p inhibits proliferation, migration, invasion and EMT by degrading ß-catenin.

Long Noncoding RNA RP11-334E6.12 Promotes the Proliferation, Migration and Invasion of Breast Cancer Cells Through the EMT Pathway by Activating the STAT3 Cascade.

BACKGROUND: RP11-334E6.12 is a dysregulated long noncoding RNA (lncRNA) that has never been studied in breast cancer. The biological function and potential mechanism of RNA RP11-334E6.12 in tumorigenesis are still unknown. METHODS: We scanned the Cancer Genome Atlas (TCGA) database and identified RP11-334E6.12 as one of the most dysregulated lncRNAs. The level of RP11-334E6.12 was assessed in breast cancer (BC) tissue samples and BC cell lines. The survival and RP11-334E6.12 expression of patients were analysed. The biological influence of RP11-334E6.12 on BC cell lines was studied using proliferation, Transwell migration, and invasion assays. RESULTS: RP11-334E6.12 was upregulated in both the TCGA database and our own database. Moreover, survival analyses indicated that RP11-334E6.12 was related to poor overall survival. Moreover, RP11-334E6.12 promoted the proliferation, migration and invasion of BC cells. RP11-334E6.12 promotes the epithelial mesenchymal transition of BC by activating the STAT3 pathway. CONCLUSION: Taken together, our results demonstrate that RP11-334E6.12 is associated with the progression of breast cancer. Our findings indicate that long noncoding RNA RP11-334E6.12 promotes the proliferation, migration and invasion of breast cancer cells by activating the STAT3 pathway.

Delivering SaCas9 mRNA by lentivirus-like bionanoparticles for transient expression and efficient genome editing.

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) system discovered using bacteria has been repurposed for genome editing in human cells. Transient expression of the editor proteins (e.g. Cas9 protein) is desirable to reduce the risk of mutagenesis from off-target activity. Using the specific interaction between bacteriophage RNA-binding proteins and their RNA aptamers, we developed a system able to package up to 100 copies of Staphylococcus aureus Cas9 (SaCas9) mRNA in each lentivirus-like bionanoparticle (LVLP). The SaCas9 LVLPs mediated transient SaCas9 expression and achieved highly efficient genome editing in the presence of guide RNA. Lower off-target rates occurred in cells transduced with LVLPs containing SaCas9 mRNA, compared with cells transduced with adeno-associated virus or lentivirus expressing SaCas9. Our LVLP system may be useful for efficiently delivering Cas9 mRNA to cell lines and primary cells for in vitro and in vivo gene editing applications.

Status quo and curriculum intervention of sexual psychological health during puberty in middle school / 中国学校卫生

Objective@#To explore the influence of comprehensive sexuality education (CSE) course based on International Technical Guidance onthe sexual psychological health of middle school students during puberty, and to provide a reference for mental health promotion.@*Methods@#This study used Adolescent Sexual Psychological Health Questionnaire as measuring tool and self-made textbook on sexuality education entitled Love and Life: Junior High School Students’ Sexual Health Education Textbook as intervention. Measurements were set before and after the first semester together with the end of the second semester, respectively were pretest, intermediate test and posttest.@*Results@#The sexual psychological health of middle school students was in the medium level, and girls(3.51±0.40) were generally better than boys(3.44±0.37)(t=3.62, P<0.05). According to one-way analysis of variance, the main effect of three dimensions of sexual health-sexual cognition(3.31±0.81, 3.68±0.80, 4.37±0.61), sexual values(3.43±0.51, 3.55±0.54, 3.85±0.58) and sexual adaptation(3.63±0.41, 3.85±0.49, 4.09±0.58) and the total score(3.51±0.39, 3.74±0.46, 4.10±0.47) before, during and after the acceptance of comprehensive sexuality education was significant(F=252.18, 281.68, 113.54, 114.60, P<0.05).@*Conclusion@#Comprehensive sexuality education course has a significant effect on improving sexual psychological health among junior high school students.