Role of MicroRNA-7 (MiR-7) in Cancer Physiopathology

miRNAs are non-coding RNA sequences of approximately 22 nucleotides that interact with genes by inhibiting their translation through binding to their 3′ or 5′ UTR regions. Following their discovery, the role they play in the development of various pathologies, particularly cancer, has been studied. In this context, miR-7 is described as an important factor in the development of cancer because of its role as a tumor suppressor, regulating a large number of genes involved in the development and progression of cancer. Recent data support the function of miR-7 as a prognostic biomarker in cancer, and miR-7 has been proposed as a strategy in cancer therapy. In this work, the role of miR-7 in various types of cancer is reviewed, illustrating its regulation, direct targets, and effects, as well as its possible relationship to the clinical outcome of cancer patients.     

食源性MRSA氨基糖苷类耐药基因多重PCR方法建立

目的:了解食源性金黄色葡萄球菌中耐甲氧西林金黄色葡萄球菌（methicillin-resistant Staphylococcus aureus,MRSA）及对氨基糖苷类庆大霉素、卡那霉素抗生素的耐药性情况,并建立快速检测鉴定金黄色葡萄球菌耐药性多重PCR方法。方法:对金黄色葡萄球菌进行增菌培养,并提取DNA作为模板,以nuc基因作为菌属鉴定基因,mec A基因作为MRSA检测基因,aac A-aph D及aph（3’）-Ⅲa基因作为耐氨基糖苷类庆大霉素、卡那霉素的检测目的基因,建立四重PCR检测方法并进行特异性及灵敏度评价;利用所建立的方法检测72株食品及食物中毒患者来源的金黄色葡萄球菌。结果:成功建立四重PCR检测方法,且72株金黄色葡萄球菌均有nuc基因检出,mec A基因与MRSA检测符合率达100%,aac A-aph D、aph（3’）-Ⅲa基因与庆大霉素、卡那霉素耐药菌株的符合率达95.12%。结论:本实验所建立的多重PCR方法灵敏度高、特异性好,可以快速检测出MRSA,并对氨基糖苷类庆大霉素、卡那霉素耐药菌株检测具有较高的准确率。      

脱羧酶基因ARO10的过量表达及其对Saccharomy cescerevisiae的β-苯乙醇合成代谢影响

为了验证脱羧酶在S.cerevisiaeβ-苯乙醇合成途径中的调控作用,本文从S.cerevisiae S288C中克隆脱羧酶基因ARO10,并构建由3-磷酸甘油酸激酶基因PGK1组成型强启动子控制的ARO10基因表达载体pYES2-Ppgk-ARO10,将重组载体导入S.cerevisiae S288C,研究ARO10基因过量表达对重组菌株中β-苯乙醇合成的影响。经摇瓶实验测定,携带pYES2-Ppgk-ARO10的转化子SP10在发酵60h时β-苯乙醇产量达到最大量1.0g/L,较野生型的对照菌提高16.3%。研究结果表明,脱羧酶是S.cerevisiae S288C中β-苯乙醇生物合成途径的关键酶之一,增加ARO10基因表达量有利于提高β-苯乙醇产量,研究为构建β-苯乙醇高产工程菌株奠定了重要基础。      

深度学习在生物序列分析领域的应用进展

随着生物技术的不断发展和生物学数据的大量产出,传统生物学数据分析方式不足以应对日益复杂庞大的生物序列数据. 面对这种情况,国内外学者逐步将深度学习应用到生物学分析中,利用其处理高维数据的优势,取得了一系列进展,并成为生物序列数据分析中的研究热门. 为了更好地了解深度学习在生物序列数据分析领域中的新进展,对该领域研究现状进行了综述. 首先,介绍深度学习应用到生物序列数据分析中的重要意义;其次,对目前应用领域中具有代表性的深度学习模型进行阐述;然后,分析深度学习在生物学领域的应用研究现状;最后,说明目前深度学习在生物学领域中的局限性,并进一步提出未来发展应考虑的因素.

     

Oligonucleotide Insecticides for Green Agriculture: Regulatory Role of Contact DNA in Plant–Insect Interactions

Insects vastly outnumber us in terms of species and total biomass, and are among the most efficient and voracious consumers of plants on the planet. As a result, to preserve crops, one of the primary tasks in agriculture has always been the need to control and reduce the number of insect pests. The current use of chemical insecticides leads to the accumulation of xenobiotics in ecosystems and a decreased number of species in those ecosystems, including insects. Sustainable development of human society is impossible without useful insects, so the control of insect pests must be effective and selective at the same time. In this article, we show for the first time a natural way to regulate the number of insect pests based on the use of extracellular double-stranded DNA secreted by the plant Pittosporum tobira. Using a principle similar to one found in nature, we show that the topical application of artificially synthesized short antisense oligonucleotide insecticides (olinscides, DNA insecticides) is an effective and selective way to control the insect Coccus hesperidum. Using contact oligonucleotide insecticide Coccus-11 at a concentration of 100 ng/μL on C. hesperidum larvae resulted in a mortality of 95.59 ± 1.63% within 12 days. Green oligonucleotide insecticides, created by nature and later discovered by humans, demonstrate a new method to control insect pests that is beneficial and safe for macromolecular insect pest management.     

Genome-Wide Identification of the CER Gene Family and Significant Features in Climate Adaptation of Castanea mollissima

The plant cuticle is the outermost layer of the aerial organs and an important barrier against biotic and abiotic stresses. The climate varies greatly between the north and south of China, with large differences in temperature and humidity, but Chinese chestnut is found in both regions. This study investigated the relationship between the wax layer of chestnut leaves and environmental adaptation. Firstly, semi-thin sections were used to verify that there is a significant difference in the thickness of the epicuticular wax layer between wild chestnut leaves in northwest and southeast China. Secondly, a whole-genome selective sweep was used to resequence wild chestnut samples from two typical regional populations, and significant genetic divergence was identified between the two populations in the CmCER1-1, CmCER1-5 and CmCER3 genes. Thirty-four CER genes were identified in the whole chestnut genome, and a series of predictive analyses were performed on the identified CmCER genes. The expression patterns of CmCER genes were classified into three trends—upregulation, upregulation followed by downregulation and continuous downregulation—when chestnut seedlings were treated with drought stress. Analysis of cultivars from two resource beds in Beijing and Liyang showed that the wax layer of the northern variety was thicker than that of the southern variety. For the Y-2 (Castanea mollissima genome sequencing material) cultivar, there were significant differences in the expression of CmCER1-1, CmCER1-5 and CmCER3 between the southern variety and the northern one-year-grafted variety. Therefore, this study suggests that the CER family genes play a role in environmental adaptations in chestnut, laying the foundation for further exploration of CmCER genes. It also demonstrates the importance of studying the adaptation of Chinese chestnut wax biosynthesis to the southern and northern environments.     

Male Rat Offspring Are More Impacted by Maternal Obesity Induced by Cafeteria Diet than Females—Additive Effect of Postweaning Diet

Maternal obesity increases the risk of health complications in offspring, but whether these effects are exacerbated by offspring exposure to unhealthy diets warrants further investigation. Female Sprague-Dawley rats were fed either standard chow (n = 15) or ‘cafeteria’ (Caf, n = 21) diets across pre-pregnancy, gestation, and lactation. Male and female offspring were weaned onto chow or Caf diet (2–3/sex/litter), forming four groups; behavioural and metabolic parameters were assessed. At weaning, offspring from Caf dams were smaller and lighter, but had more retroperitoneal (RP) fat, with a larger effect in males. Maternal Caf diet significantly increased relative expression of ACACA and Fasn in male and female weanling liver, but not CPT-1, SREBP and PGC1; PPARα was increased in males from Caf dams. Maternal obesity enhanced the impact of postweaning Caf exposure on adult body weight, RP fat, liver mass, and plasma leptin in males but not females. Offspring from Caf dams appeared to exhibit reduced anxiety-like behaviour on the elevated plus maze. Hepatic CPT-1 expression was reduced only in adult males from Caf fed dams. Post weaning Caf diet consumption did not alter liver gene expression in the adult offspring. Maternal obesity exacerbated the obesogenic phenotype produced by postweaning Caf diet in male, but not female offspring. Thus, the impact of maternal obesity on adiposity and liver gene expression appeared more marked in males. Our data underline the sex-specific detrimental effects of maternal obesity on offspring.     

Clinical Breakpoint of Apramycin to Swine Salmonella and Its Effect on Ileum Flora

The purpose of this study was to establish the clinical breakpoint (CBP) of apramycin (APR) against Salmonella in swine and evaluate its effect on intestinal microbiota. The CBP was established based on three cutoff values of wild-type cutoff value (CO_WT), pharmacokinetic-pharmadynamic (PK/PD) cutoff value (CO_PD) and clinical cutoff value (CO_CL). The effect of the optimized dose regimen based on ex vivo PK/PD study. The evolution of the ileum flora was determined by the 16rRNA gene sequencing and bioinformatics. This study firstly established the CO_WT, CO_PD in ileum, and CO_CL of APR against swine Salmonella, the value of these cutoffs were 32 µg/mL, 32 µg/mL and 8 µg/mL, respectively. According to the guiding principle of the Clinical Laboratory Standards Institute (CLSI), the final CBP in ileum was 32 µg/mL. Our results revealed the main evolution route in the composition of ileum microbiota of diarrheic piglets treated by APR. The change of the abundances of Bacteroidetes and Euryarchaeota was the most obvious during the evolution process. Methanobrevibacter, Prevotella, S24-7 and Ruminococcaceae were obtained as the highest abundance genus. The abundance of Methanobrevibacter increased significantly when APR treatment carried and decreased in cure and withdrawal period groups. The abundance of Prevotella in the tested groups was significantly lower than that in the healthy group. A decreased of abundance in S24-7 was observed after Salmonella infection and increased slightly after cure. Ruminococcaceae increased significantly after Salmonella infection and decreased significantly after APR treatment. In addition, the genera of Methanobrevibacter and Prevotella were defined as the key node. Valine, leucine and isoleucine biosynthesis, D-Glutamine and D-glutamate metabolism, D-Alanine metabolism, Peptidoglycan and amino acids biosynthesis were the top five Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways in the ileum microbiota of piglets during the Salmonella infection and APR treatment process. Our study extended the understanding of dynamic shift of gut microbes during diarrheic piglets treated by APR.     

CRISPR Therapeutics for Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is an X-linked recessive neuromuscular disorder with a prevalence of approximately 1 in 3500–5000 males. DMD manifests as childhood-onset muscle degeneration, followed by loss of ambulation, cardiomyopathy, and death in early adulthood due to a lack of functional dystrophin protein. Out-of-frame mutations in the dystrophin gene are the most common underlying cause of DMD. Gene editing via the clustered regularly interspaced short palindromic repeats (CRISPR) system is a promising therapeutic for DMD, as it can permanently correct DMD mutations and thus restore the reading frame, allowing for the production of functional dystrophin. The specific mechanism of gene editing can vary based on a variety of factors such as the number of cuts generated by CRISPR, the presence of an exogenous DNA template, or the current cell cycle stage. CRISPR-mediated gene editing for DMD has been tested both in vitro and in vivo, with many of these studies discussed herein. Additionally, novel modifications to the CRISPR system such as base or prime editors allow for more precise gene editing. Despite recent advances, limitations remain including delivery efficiency, off-target mutagenesis, and long-term maintenance of dystrophin. Further studies focusing on safety and accuracy of the CRISPR system are necessary prior to clinical translation.