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The rapid overcompensatory growth that appears when cyanobacteria are supplied with adequate resources after a period of resource deprivation might contribute to the occurrence of cyanobacterial blooms. We investigated the changing characteristics of overcompensatory growth and serine/threonine kinase (STK) genes expression of cyanobacterium Microcystis aeruginosa in response to light limitation. The results showed M. aeruginosa exhibited overcompensatory growth for 2 days after light recovery, during which the increase in growth was inversely related to light intensity. Expression of STK genes, such as spkD, was upregulated significantly at 0.5–4 h after light recovery (P < 0.05). To investigate the function of STK genes in the overcompensatory growth, M. aeruginosa spkD was heterologously expressed in Synechocystis. Transgenic Synechocystis exhibited greater and longer overcompensatory growth than wild-type Synechocystis after light recovery. Relative expression levels of STK genes in transgenic Synechocystis were significantly higher than those in wild-type Synechocystis at 24 h of light recovery (P < 0.05). Heterologous expression of Microcystis spkD might stimulate overcompensatory growth of Synechocystis by affecting its STK gene expression. HIGHLIGHTS Light limitation induced overcompensatory growth of Microcystis.; Light limitation affected expression of most STK genes of Microcystis.; Heterologous expression of Microcystis spkD enhanced and prolonged light-limitation-induced overcompensatory growth of transgenic Synechocystis.; Heterologous expression of Microcystis spkD stimulated relative expression levels of STK genes in transgenic Synechocystis.

FOXOs transcription factors not only play key roles in glucose metabolism, muscle atrophy and energy homeostasis but also play crucial transcriptional regulatory roles in the cell's metabolism, orchestrating programs of gene expression that regulate cell apoptosis, cell-cycle progression and oxidative stress resistance. However, the specific function of FOXOs promoting fibroblasts proliferation and apoptosis are still unknown. Thus, we used the High-Resolution Melting (HRM) and RNA interference methods to detect SNPs and function. We found one SNP in the exon of FOXO1, three SNPs were identified in the exon of FOXO3, and three SNPs and production traits were significantly different. The siRNA sequence of yak FOXO1 and FOXO3 were transfected into the yak fibroblasts, and effects were detected by a series of assays to reveal the function in yak fibroblasts. The results demonstrated that down-regulated expression of FOXO1 and FOXO3 resulted in up-regulated the expression of BAX, Caspase9 and Caspase3, and down-regulated the expression level of anti-apoptotic gene of BCL2. The apoptotic situation was consistent with results of the flow cytometry and Tunel test cell cycle and cell vitality results revealed that knockdown FOXO1 and FOXO3 resulted in increased P27 expression level and decreased CyclinD1. Meanwhile, cell vitality was also decreased. These results demonstrated that FOXO1 and FOXO3 are two novel regulatory factors to suppress cells proliferation and promote cells apoptosis. Furthermore, these results provide evidence that FOXO1 and FOXO3 play a functional role in cell apoptosis.

Summary Ablation of Slc22a14 causes male infertility in mice, but the underlying mechanisms remain unknown. Here, we show that SLC22A14 is a riboflavin transporter localized at the inner mitochondrial membrane of the spermatozoa mid-piece and show by genetic, biochemical, multi-omic, and nutritional evidence that riboflavin transport deficiency suppresses the oxidative phosphorylation and reprograms spermatozoa energy metabolism by disrupting flavoenzyme functions. Specifically, we find that fatty acid β-oxidation (FAO) is defective with significantly reduced levels of acyl-carnitines and metabolites from the TCA cycle (the citric acid cycle) but accumulated triglycerides and free fatty acids in Slc22a14 knockout spermatozoa. We demonstrate that Slc22a14-mediated FAO is essential for spermatozoa energy generation and motility. Furthermore, sperm from wild-type mice treated with a riboflavin-deficient diet mimics those in Slc22a14 knockout mice, confirming that an altered riboflavin level causes spermatozoa morphological and bioenergetic defects. Beyond substantially advancing our understanding of spermatozoa energy metabolism, our study provides an attractive target for the development of male contraceptives., Graphical abstract, Highlights • Slc22a14 deficiency results in decreased sperm motility and male infertility • Slc22a14 ablation disrupts fatty acid β-oxidation and flavoenzyme activity • Slc22a14 is a riboflavin transporter located at inner mitochondrial membrane in sperm, Long-chain fatty acid β-oxidation is an important energy source during epididymal maturation of spermatozoa. Kuang et al. show that Slc22a14 is a riboflavin transporter located at the inner mitochondrial membrane. Slc22a14 deficiency in the spermatozoa mid-piece disrupts the riboflavin transport and subsequently alters flavoenzyme-mediated bioenergetic metabolism, resulting in male infertility.

Spermatogenesis is a dynamic developmental process in which spermatogonial stem cells proliferate, differentiate and mature into functional spermatozoa. These processes require an accurate gene regulation network. Here, we investigated the dynamic changes that occur during spermatogenesis through a combination of histological and transcriptome analyses of different developmental stages of the testis. We constructed 18 testis transcriptome libraries, and the average length, N50, and GC content of the unigenes were 1,795 bp; 3,240 bp and 49.25%, respectively. Differentially expressed genes (DEGs) that were related to germ cell proliferation and maturation, such as NANOS3, RARs, KIFs, steroid hormone synthesis-related genes and receptor genes, were identified between pairs of testis at different developmental stages. Gene ontology annotation and pathway analyses were conducted on DEGs with specific expression patterns involved in the regulation of spermatogenesis. Nine important pathways such as steroid hormone biosynthesis related to spermatogenesis were identified. A total of 21 modules that ranged from 49 to 7,448 genes were designed by a weighted gene co-expression network analysis. Furthermore, a total of 83 candidate miRNA were identified by computational methods. Our study provides the first transcriptomic evidence for differences in gene expression between different developmental stages of spermatogenesis in turbot (Scophthalmus maximus).

Background: The prognostic significance of podoplanin (PDPN) in tumor cells for cancer patients’ survival remains controversial. Therefore, we performed this meta-analysis to clarify the relationship between the podoplanin-positive tumor cells and cancer prognosis. Method: Eligible studies were identified by searching the Pubmed and EBSCO online databases up to August 2019. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to evaluate the correlation between podoplanin expression and overall survival (OS) and/or disease-free survival (DFS) and odds ratios (ORs) with 95% CIs severed as the summarized statistics for clinicopathological characteristic. Results: A total of 2155 patients from 21 eligible studies were included. The results revealed that high expression of podoplanin was associated with a poor survival rate in cancer patients. Further subgroup analysis stratified by tumor type showed that podoplanin-positive tumor cell infiltration had a negative prognostic effect associated with survival in esophageal cancer and oropharyngeal cancer. In addition, high expression of these cells was significantly associated with N stage, T stage, TNM stage and vascular invasion. Conclusion: Our study suggests the over-expression of podoplanin might be a significant prognostic indicator for patients with esophageal and oropharyngeal cancer.

To understand multidrug resistance gene expression in reactive astrocytes, the present study involved stimulated astrocytes with tumor necrosis factor (TNF)‑α and determined gene expression by reverse transcription‑quantitative polymerase chain reaction and western blot analysis. Stimulation induced P‑glycoprotein (gp) and multidrug resistance‑associated protein (MRP0) 1 expression, which peaked by 24 h. Interestingly, the expression of P‑gp and Mrp1 correlated with cell proliferation. Therefore, reactivation of astrocytes may increase P‑gp and Mrp1 expression through TNF‑α and nuclear factor (NF)‑κB signaling. To the best of the authors' knowledge, the present study is the first to demonstrate that in vitro activated astrocytes likely induced P‑gp and Mrp1 expression by increasing NF‑κB expression. The results of the present study provide a novel insight into the mechanism of refractory epilepsy and suggest inhibiting cytokine signaling may block multidrug resistance.

To understand the neural origins of rhythmic behavior one must characterize the central pattern generator circuit and quantify the population size needed to sustain functionality. Breathing-related interneurons of the brainstem pre-Bötzinger complex (preBötC) that putatively comprise the core respiratory rhythm generator in mammals are derived from Dbx1-expressing precursors. Here, we show that selective photonic destruction of Dbx1 preBötC neurons in neonatal mouse slices impairs respiratory rhythm but surprisingly also the magnitude of motor output; respiratory hypoglossal nerve discharge decreased and its frequency steadily diminished until rhythm stopped irreversibly after 85±20 (mean ± SEM) cellular ablations, which corresponds to ∼15% of the estimated population. These results demonstrate that a single canonical interneuron class generates respiratory rhythm and contributes in a premotor capacity, whereas these functions are normally attributed to discrete populations. We also establish quantitative cellular parameters that govern network viability, which may have ramifications for respiratory pathology in disease states. DOI: http://dx.doi.org/10.7554/eLife.03427.001, eLife digest Our first breath, moments after we are born, is the result of a pattern of activity in our brain that started in the embryo and will continue almost effortlessly until we die. Like other rhythmic activities, such as walking and swimming, breathing originates from circuits of neurons in the brain that generate patterns. These circuits pass messages to other cells that translate them into the physical movements required to take a breath. Interrupting these patterns by injury or illness can lead to breathing disorders or cause death. Previous studies have identified a class of neuron, which all express a specific gene, that is necessary for breathing. Mice born without this class of cell failed to ever take a breath and died at birth. These neurons are found in part of the brainstem and can continue to generate rhythm even when this section of the brainstem is removed from newborn mice and cut into very thin slices. However, it is unclear how many of these neurons are needed to maintain a breathing rhythm. Wang et al. used a laser to destroy the breathing rhythm-generating neurons in these slices one at a time and found that the rhythm of breathing in (i.e., inspiration) stopped after ∼15% of the neurons were destroyed. This suggests that a high percentage of these neurons must be maintained for breathing to continue normally. Wang et al. also discovered that destroying the rhythm-generating neurons reduced the strength of the signals sent from the brainstem to trigger the movements that cause breathing in. This suggests that the same class of neurons also sends messages to the muscles involved in breathing; it was previously thought that a separate class of cell in the same part of the brain sent these messages. Studies involving live animals are now needed to confirm the results. If confirmed, the findings may be used to develop new treatments for a number of breathing disorders. Medications that boost the signals sent to the muscles by these neurons might be useful for treating sleep apnea. Wang et al. also suggest that medications that boost rhythm generation might be useful for premature infants with breathing difficulties and people with drug-induced breathing problems. Moreover, finding ways to maintain breathing rhythms with fewer of these neurons may help those with neurodegenerative disorders, which cause cells in the brain to be lost. DOI: http://dx.doi.org/10.7554/eLife.03427.002

Cells of monocytic lineage can initiate extravascular fibrin deposition via expression of blood coagulation mediators. This report is about experiments on three mechanisms with the potential to modulate monocyte-initiated coagulation. Monocyte procoagulant activity was examined as a function of lipid cofactor, protein cofactor, and specific inhibitor expression during short-term culture in vitro. Lipid cofactor activity was measured as the initial rate of factor X activation by intrinsic-pathway components, the assembly of which depends on this cofactor. Lipid cofactor activity levels changed by < 30% during 48-h culture. Protein cofactor, i.e., tissue factor (TF) antigen was measured by enzyme immunoassay. It increased from 461 pg/ml to a maximum value of 3,550 pg/ml at 24 h and remained at 70% of this value. Specific TF activity, measured as factor VII-dependent factor X activation rate, decreased from 54 to 18 nM FXa/min between 24 and 48 h. TF activity did not correlate well with either lipid cofactor or TF protein levels. In contrast, the decrease in TF activity coincided in time with maximal expression of tissue factor pathway inhibitor (TFPI) mRNA, which was determined using reverse transcriptase polymerase chain reaction (RT-PCR), and with maximal TFPI protein levels measured by immunoassay. The number of mRNA copies coding for TFPI and TF in freshly isolated blood monocytes were 46 and 20 copies/cells, respectively. These values increased to 220 and 63 copies/cell during short-term cell culture in the presence of endotoxin. Results demonstrate concomitant expression by monocytes of genes coding for both the essential protein cofactor and the specific inhibitor of the extrinsic coagulation pathway. Together with functional and antigenic analyses, they also imply that the initiation of blood clotting by extravascular monocyte/macrophages can be modulated locally by TFPI independently of plasma sources of the inhibitor.