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Gut microbiota play critical roles in host nutrition and metabolism. However, little is known about the genetic effects on the gut microbiota assemblages because a suitable model for investigation is lacking. In the present study, we established the reciprocal hybrid fish lineages derived from the parents with different feeding habits, namely, herbivorous blunt snout bream (Megalobrama amblycephala, BSB, 2n = 48) and carnivorous topmouth culter (Culter alburnus, TC, 2n = 48). We investigated the genetic effects on gut microbiota assemblages by using 16S rRNA gene sequencing. The results showed that the gut characteristics (structure, relative gut length, relative gut mass, and Zihler’s index) differed between the two types of hybrids and the two parents. In particular, a strong correlation between genotype and gut microbial assemblages indicated that host genetic (subgenome) significantly altered the gut microbial communities. In addition, the microbial structures (composition and abundance) in the two types of hybrids were more similar to those in BSB parent (P > 0.05) than to those in TC parent (P < 0.05), and the cellulase contents in the gut (produced by gut microbes) also showed the similar results. The results suggested that the host genomic interaction (mainly subgenome domination) had a sizeable effect on shaping the gut microbiota assemblages in reciprocal hybrid fish. This study enriches our understanding of the relationship between host genetic and gut microbiota assemblages, and provides insight into gut microbiota and metabonomics.

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[ 18 F]fluoro-2-deoxyglucose (FDG) positron emission tomography (PET)-computed tomography (CT) is a functional imaging modality based on glucose metabolism. The association between the maximum standardized uptake value (SUV max) from 18 F-FDG PET-CT scanning and epidermal growth factor receptor (EGFR) mutation status has, to the best of our knowledge, not previously been fully elucidated, and the potential mechanisms by which EGFR mutations alter FDG uptake are largely unknown. A total of 157 patients who were pathologically diagnosed with non-small cell lung cancer (NSCLC) who underwent EGFR mutation testing and PET-CT pretreatment between June 2015 and October 2017 were retrospectively analyzed. χ 2 and univariate analyses were performed to identify the contributors to EGFR mutation. The receiver operating characteristic (ROC) curve was analyzed, and the area under the curve (AUC) was calculated. Glucose transporter 1 (GLUT1) and NADPH oxidase 4 (NOX4) expression, and reactive oxygen species (ROS) activity were detected in the A549 (wild-type), PC-9 (EGFR mutation-positive, EGFR exon 19del) and NCI-H1975 (EGFR mutation-positive, combined with L858R and T790M substitution) cell lines. A total of 109 patients who met the criteria were enrolled, and 63 of those tested as EGFR mutation-positive. The SUV max values were significantly lower in patients with EGFR mutations (mean, 6.52±0.38) compared with in patients with wild-type EGFR (mean, 9.37±0.31; P<0.001). Using univariate analysis, EGFR mutation status was significantly associated with sex, smoking status, tumor histology and SUV max of the primary tumor. In the multivariate analysis, smoking status (never-smoking), histopathology (adenocarcinoma) and SUV max (≤9.91) were the statistically significant predictors of EGFR mutations. ROC curve analysis identified that the SUV max cutoff point was 9.92, for which the AUC was 0.75 (95% confidence interval, 0.68-0.83). Reverse transcription-polymerase chain reaction indicated that the GLUT1 mRNA decreased in the PC-9 and NCI-H1975 cell lines compared with the A549 cell line (0.82±0.07 and 0.72±0.04 vs. 0.98±0.04, respectively; P<0.05) and decreased ROS activity was observed in the PC-9 cell line. Furthermore, the expression of NOX4 mRNA decreased by 20% in PC-9 (P<0.01) and by 14% (P<0.05) in NCI-H1975 cells. In addition, NOX4 protein expression decreased by 13% in PC-9 and by 16% in NCI-H1975 cells (both P<0.05) compared with the A549 cell line. The SUV max could be considered to effectively predict EGFR mutation status of patients with NSCLC, and the EGFR mutation status may alter FDG uptake partially via the NOX4/ROS/GLUT1 axis.

The pine moth Dendrolimus punctatus (Walker) is a common insect pest that confers serious damage to conifer forests in south of China. Extensive physiology and ecology studies on D. punctatus have been carried out, but the lack of genetic information has limited our understanding of the molecular mechanisms behind its development and resistance. Using RNA-seq approach, we characterized the transcriptome of this pine moth and investigated its developmental expression profiles during egg, larval, pupal, and adult stages. A total of 107.6 million raw reads were generated that were assembled into 70,664 unigenes. More than 30% unigenes were annotated by searching for homology in protein databases. To better understand the process of metamorphosis, we pairwise compared four developmental phases and obtained 17,624 differential expression genes. Functional enrichment analysis of differentially expressed genes showed positive correlation with specific physiological activities of each stage, and these results were confirmed by qRT-PCR experiments. This study provides a valuable genomic resource of D. punctatus covering all its developmental stages, and will promote future studies on biological processes at the molecular level.

Fibroblast activation protein (FAP), a type II transmembrane serine protease, is highly expressed in more than 90% of epithelial tumors and is closely associated with various tumor invasion, metastasis, and prognosis. Using FAP as a target, various FAP inhibitors (FAPIs) have been developed, most of which have nanomolar levels of FAP affinity and high selectivity and are used for positron emission tomography (PET) imaging of different tumors. We have conducted a systematic review of the available data; summarized the biological principles of FAPIs for PET imaging, the synthesis model, and metabolic characteristics of the radiotracer; and compared the respective values of FAPIs and the current mainstream tracer 18F-Fludeoxyglucose (18F-FDG) in the clinical management of tumor and non-tumor lesions. Available research evidence indicates that FAPIs are a molecular imaging tool complementary to 18F-FDG and are expected to be the new molecule of the century with better imaging effects than 18F-FDG in a variety of cancers, including gastrointestinal tumors, liver tumors, breast tumors, and nasopharyngeal carcinoma.

BackgroundHybridization and polyploidization are regarded as the major driving forces in plant speciation, diversification, and ecological adaptation. Our knowledge regarding the mechanisms of duplicated-gene regulation following genomic merging or doubling is primarily derived from plants and is sparse for vertebrates.ResultsWe successfully obtained an F1 generation (including allodiploid hybrids and triploid hybrids) from female Megalobrama amblycephala Yih (BSB, 2n = 48) × male Xenocypri davidi Bleeker (YB, 2n = 48). The duplicated-gene expression patterns of the two types of hybrids were explored using RNA-Seq data. In total, 5.44 × 108 (69.32 GB) clean reads and 499,631 assembled unigenes were obtained from the testis transcriptomes. The sequence similarity analysis of 4265 orthologs revealed that the merged genomes were dominantly expressed in different ploidy hybrids. The differentially expressed genes in the two types of hybrids were asymmetric compared with those in both parents. Furthermore, the genome-wide expression level dominance (ELD) was biased toward the maternal BSB genome in both the allodiploid and triploid hybrids. In addition, the dosage-compensation mechanisms that reduced the triploid expression levels to the diploid state were determined in the triploid hybrids.ConclusionsOur results indicate that divergent genomes undergo strong interactions and domination in allopolyploid offspring. Genomic merger has a greater effect on the gene-expression patterns than genomic doubling. The various expression mechanisms (including maternal effect and dosage compensation) in different ploidy hybrids suggest that the initial genomic merger and doubling play important roles in polyploidy adaptation and evolution.Electronic supplementary materialThe online version of this article (10.1186/s12864-018-4883-7) contains supplementary material, which is available to authorized users.