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The rate of photosynthesis depends on the CO2 partial pressure near Rubisco, Cc, which is commonly calculated by models using the overall mesophyll resistance. Such models do not explain the difference between the CO2 level in the intercellular air space and Cc mechanistically. This problem can be overcome by reaction-diffusion models for CO2 transport, production and fixation in leaves. However, most reaction-diffusion models are complex and unattractive for procedures that require a large number of runs, like parameter optimisation. This study provides a simpler reaction-diffusion model. It is parameterized by both leaf physiological and leaf anatomical data. The anatomical data consisted of the thickness of the cell wall, cytosol and stroma, and the area ratios of mesophyll exposed to the intercellular air space to leaf surfaces and exposed chloroplast to exposed mesophyll surfaces. The model was used directly to estimate photosynthetic parameters from a subset of the measured light and CO2 response curves; the remaining data were used for validation. The model predicted light and CO2 response curves reasonably well for 15 days old tomato (cv. Admiro) leaves, if (photo)respiratory CO2 release was assumed to take place in the inner cytosol or in the gaps between the chloroplasts. The model was also used to calculate the fraction of CO2 produced by (photo)respiration that is re-assimilated in the stroma, and this fraction ranged from 56 to 76%. In future research, the model should be further validated to better understand how the re-assimilation of (photo)respired CO2 is affected by environmental conditions and physiological parameters. [ABSTRACT FROM AUTHOR]

Ureaplasma spp. have gained increasing recognition as pathogens in both adult and neonatal patients with multiple clinical presentations. However, the clonality of this organism in the male population and infertile couples in China is largely unknown. In this study, 96 (53 U. parvum and 43 U. urealyticum) of 103 Ureaplasma spp. strains recovered from genital specimens from male patients and 15 pairs of infertile couples were analyzed using multilocus sequence typing (MLST)/expanded multilocus sequence typing (eMLST) schemes. A total of 39 sequence types (STs) and 53 expanded sequence types (eSTs) were identified, with three predominant STs (ST1, ST9 and ST22) and eSTs (eST16, eST41 and eST82). Moreover, phylogenetic analysis revealed two distinct clusters that were highly congruent with the taxonomic differences between the two Ureaplasma species. We found significant differences in the distributions of both clusters and sub-groups between the male and female patients (P < 0.001). Moreover, 66.7% and 40.0% of the male and female partners of the infertile couples tested positive for Ureaplasma spp. The present study also attained excellent agreement of the identification of both Ureaplasma species between paired urine and semen specimens from the male partners (k > 0.80). However, this concordance was observed only for the detection of U. urealyticum within the infertile couples. In conclusion, the distributions of the clusters and sub-groups significantly differed between the male and female patients. U. urealyticum is more likely to transmit between infertile couples and be associated with clinical manifestations by the specific epidemic clonal lineages. [ABSTRACT FROM AUTHOR]

Late leaf spot (LLS) is a major foliar disease in peanut (A. hypogaea L.) worldwide, causing significant losses of potential yield in the absence of fungicide applications. Mutants are important materials to study the function of disease-related genes. In this study, the mutant line M14 was derived from cultivar Yuanza 9102 treated with EMS. Yuanza 9102 was selected from an interspecific cross of cultivar Baisha 1016 with A. diogoi, and is resistant to several fungal diseases. By contrast, the M14 was highly susceptible to late leaf spot. RNA-Seq analysis in the leaf tissues of the M14 and its wild type Yuanza 9102 under pathogen challenge showed 2219 differentially expressed genes including1317 up-regulated genes and 902 down-regulated genes. Of these genes, 1541, 1988, 1344, 643 and 533 unigenes were obtained and annotated by public protein databases of SwissPort, TrEMBL, gene ontology (GO), KEGG and clusters of orthologous groups (COG), respectively. Differentially expressed genes (DEGs) showed that expression of inducible pathogenesis-related (PR) proteins was significantly up-regulated; in the meantime DEGs related to photosynthesis were down-regulated in the susceptible M14 in comparison to the resistant WT. Moreover, the up-regulated WRKY transcription factors and down-regulated plant hormones related to plant growth were detected in the M14. The results suggest that down-regulated chloroplast genes, up-regulated WRKY transcription factors, and depressed plant hormones related to plant growth in the M14 might coordinately render the susceptibility though there was a significant high level of PRs. Those negative effectors might be triggered in the susceptible plant by fungal infection and resulted in reduction of photosynthesis and phytohormones and led to symptom formation. [ABSTRACT FROM AUTHOR]

Nicotinamide N-methyltransferase (NNMT) has been found involved in cell proliferation of several malignancies. However, the functional role of NNMT in breast cancer has not been elucidated. In the present study, we showed that NNMT was selectively expressed in some breast cancer cell lines, down-regulation of NNMT expression in Bcap-37 and MDA-MB-231 cell lines by NNMT shRNA significantly inhibited cell growth in vitro, decreased tumorigenicity in mice and induced apoptosis. The silencing reciprocal effect of NNMT was confirmed by over-expressing NNMT in the MCF-7 and SK-BR-3 breast cancer cell lines which lack constitutive expression of NNMT. In addition, down-regulation of NNMT expression resulted in reducing expression of Bcl-2 and Bcl-xL, up-regulation of Bax, Puma, cleaved caspase-9, cleaved caspase-3 and cleaved PARP, increasing reactive oxygen species production and release of cytochrome c from mitochondria, and decreasing the phosphorylation of Akt and ERK1/2. These data suggest that down-regulation of NNMT induces apoptosis via the mitochondria-mediated pathway in breast cancer cells. [ABSTRACT FROM AUTHOR]