Search

AbstractSugar transporter proteins (STPs) play an important role in plant growth and development and stress resistance. Pepper (Capsicum annuumL.) is a significant economic crop and is widely cultivated worldwide. However, the evolution and the roles of STPgenes in the growth and development and in coping with abiotic stresses in pepper are poorly known. Here, we characterized STPgene family in pepper through integration of chromosomal location, gene structure, conserved motif, phylogeny, expression patterns in different tissues and abiotic stresses. Using bioinformatics-based methods, we identified 17 putative STPgenes in pepper. Chromosome mapping indicated that they are unevenly distributed on 9 chromosomes and there are tandem duplication events. Gene structure analysis revealed that intron numbers among these CaSTPgenes ranged from 2 to 5, except that CaSTP12and CaSTP13genes contained no introns. The phylogenetic tree of STPgenes from pepper and other plant species revealed that STPgenes were grouped into 4 subfamilies, suggesting that these gene subfamilies may have diverged from a single common ancestor prior to the mono-dicot split. Gene expression analysis based on RNA-seq data showed that three genes were expressed constitutively in all the tissues analyzed, implying that these genes might have specific function in pepper. Stress data analysis showed that the expression profiles of some members of the CaSTPgene family were altered under cold, heat, salt and hormone stress conditions. The present results will provide valuable information into the evolutionary relationships and functional divergence of the STPfamily in the future.

Landfill leachate has been identified as a significant reservoir of antibiotic resistance genes (ARGs). Metallic nanoparticles (M-NPs) increasingly incorporated into various consumer products are eventually disposed in landfills and leached into leachate. However, little is known about the impact of M-NPs on the occurrence of ARGs in leachate. Here, we investigated the changes of ARGs for 56 days in leachate exposed to different concentrations of two representative M-NPs, i.e.zinc oxide (ZnO) and zero valent iron (Fe0) NPs. The results showed that ZnO NP exposure increased ARG abundances, and Fe0NP exposure decreased ARG abundances. Most of the ARG abundances were significantly associated with mobile genetic elements (MGEs). Furthermore, the presence of ZnO and Fe0NPs induced obvious changes in bacterial community. Network analysis revealed significant bacteria-ARG co-occurrence patterns, indicating that the shifted bacterial community was an important factor explaining the changed ARG patterns. Structural equation models suggested that ZnO NP exposure increased the abundances of ARGs by dominantly driving changes in bacterial community, followed by the increase in MGEs, whereas the decreased abundances of ARGs were mainly associated with the reduction of MGEs mediated by Fe0NPs. These findings can provide a theoretical reference for future evaluation of public health risks of M-NPs and promote the mechanistic understanding of M-NP-induced ARG dissemination or attenuation in the environment.

The hypoxic microenvironment of cryptorchidism is an important factor in the impairment and fibrosis of Sertoli cells which result in blood-testis barrier (BTB) destruction and spermatogenesis loss. Recent studies have shown that melatonin, a well-known pineal hormone exerts beneficial effects against pathological fibrosis in a various of organs. However, it is still unknown whether melatonin can regulate hypoxia-induced fibrosis of Sertoli cells. In this study we evaluate melatonin levels, and its synthesizing enzymes, AANAT and HIOMT expression patterns in canine cryptorchidism and contralateral normal testis. Results show abdominal testes presented low melatonin levels and AANAT and HIOMT expression compared with testes located in the scrotum. Moreover, we established a hypoxia-induced fibrosis model in canine Sertoli cells induced by cobalt chloride (CoCl2) and found that melatonin inhibited the EMT markers expression and ECM production as well as Hif-1α expression of Sertoli cells in a dose-dependent manner. Furthermore, use of Lificiguat (synonyms YC-1, Hif-1α inhibitor) to interfere with the Hif-1α pathway showed a similar effect with melatonin suppression of the fibrosis in Sertoli cells. The results indicate that melatonin supplementation can alleviate the fibrosis process of Sertoli cells caused by hypoxia, which is associated with regulating the inhibition of Hif-1α signaling.