Citrus sinensis MYB Transcription Factor CsMYB85 Induce Fruit Juice Sac Lignification Through Interaction With Other CsMYB Transcription Factors

Varieties of Citrus are commercially important fruits that are cultivated worldwide and are valued for being highly nutritious and having an appealing flavor. Lignification of citrus fruit juice sacs is a serious physiological disorder that occurs during postharvest storage, for which the underlying transcriptional regulatory mechanisms remain unclear. In this study, we identified and isolated a candidate MYB transcription factor, CsMYB85, that is involved in the regulation of lignin biosynthesis in Citrus sinensis, which has homologs in Arabidopsis and other plants. We found that during juice sac lignification, CsMYB85 expression levels increase significantly, and therefore, suspected that this gene may control lignin biosynthesis during the lignification process. Our results indicated that CsMYB85 binds the CsMYB330 promoter, regulates its expression, and interacts with CsMYB308 in transgenic yeast and tobacco. A transient expression assay indicated that Cs4CL1 expression levels and lignin content significantly increased in fruit juice sacs overexpressing CsMYB85. At4CL1 expression levels and lignin content were also significantly increased in Arabidopsis overexpressing CsMYB85. We accordingly present convincing evidence for the participation of the CsMYB85 transcription factor in fruit juice sac lignification, and thereby provide new insights into the transcriptional regulation of this process in citrus fruits

Cloning of Toll-like Receptor 3 Gene from Schizothorax prenanti (SpTLR3), and Expressions of Seven SpTLRs and SpMyD88 after Lipopolysaccharide Induction

Toll-like receptor 3 (SpTLR3) from Schizothorax prenanti (S. prenanti) was cloned and identified, and the tissue distribution of the SpTLR3 gene was examined in this study. Moreover, the relative mRNA expression levels of myeloid differentiation factor 88 gene (SpMyD88) and seven TLR genes (SpTLR2, SpTLR3, SpTLR4, SpTLR18, SpTLR22-1, SpTLR22-2 and SpTLR22-3) from S. prenanti after lipopolysaccharide (LPS) challenge were analyzed through quantitative real-time polymerase chain reaction (qRT-PCR). The full length of SpTLR3 gene is 3097 bp, and complete coding sequence (CDS) is 2715 bp, which encodes 904 amino acids. The SpTLR3 amino acid sequence shared 43.94–100% identity with TLR3 sequences from other vertebrates; SpTLR3 was expressed in all eight tissues examined; and the highest level appeared in the liver, which was significantly higher than in all other tissues (p < 0.05), followed by the levels in the heart and muscles. LPS significantly up-regulated all eight genes in the S. prenanti tissues at 12 or 24 h (p < 0.05). Compared with the PBS control group, no significant transcripts changes were found in SpTLR2 or SpTLR3 at 12 h after LPS induction, but they were significantly up-regulated at 24 h (p < 0.001). The most abundant transcripts were found in the head kidney SpTLR22 genes after 24 h LPS induction, with high to low levels, which were SpTLR22-1 (564-fold), SpTLR22-3 (508-fold) and SpTLR22-2 (351-fold). Among these eight genes, the expression level of SpTLR4 was the least up-regulated. Overall, SpTLR4 in the head kidney was involved in the antibacterial immune response earlier, and the level was increased at 12 h with extreme significance after LPS stimulation (p < 0.001), while the other seven genes were the most significantly up-regulated at 24 h post injection. Taken together, the results suggest that SpMyD88, SpTLR2, SpTLR3, SpTLR4, SpTLR18, SpTLR22-1, SpTLR22-2 and SpTLR22-3 participate in an innate immune response stimulated by LPS, and the response intensity of the genes was organ-specific, with differing kinetics. Our findings will contribute to a more complete understanding of the roles of these TLR genes in antibacterial immunity

Association of hyperglycaemia with the placenta of GDM-induced macrosomia with normal pre-pregnancy BMI and the proliferation of trophoblast cells

The aim of this study was to identify the effect of hyperglycaemia on placentas of gestational diabetes mellitus (GDM) women with macrosomia and normal pre-pregnancy body mass index (BMI), and uncover the molecular mechanism of hyperglycaemia on trophoblast cells in vitro. GDM women with normal pre-pregnancy BMI were divided into GM group (macrosomia, n = 30) and GN group (normal birth weight, n = 35). The study showed GM group had more adverse pregnancy outcomes and higher levels of gestational weight gain, blood glucose and triglyceride. After adjustment for confounding factors, just the fasting plasma glucose level and HbA1c percentage were related to the incidence of GDM-induced macrosomia with normal pre-pregnancy BMI. Meanwhile, the fasting blood glucose was closely related to the placental weight and placental PCNA expression. Furthermore, the in vitro model for placenta showed that hyperglycaemia significantly promoted trophoblast cell proliferation and activated ERK1/2 phosphorylation. ERK1/2 inhibitor markedly suppressed hyperglycaemia-induced trophoblastic proliferation. The fasting plasma glucose and placenta are closely related with the development of GDM-induced macrosomia with normal pre-pregnancy BMI. The mechanism may be hyperglycaemia promotes trophoblast cell proliferation via ERK1/2 signalling. It provides scientific evidence for optimising outcomes of GDM women with normal pre-pregnancy BMI.IMPACT STATEMENT What is already known on this subject? Gestational diabetes mellitus (GDM) is one of the strongest risk factors correlated with macrosomia. The hyperglycaemic intrauterine environment affects not only the foetus but also the placental development and function in humans and experimental rodents. However, placental abnormalities associated with maternal diabetes have been inconsistently reported, possibly because of population differences in pre-pregnancy weight, diabetes types, glycemic control or pregnancy complication, and the molecular mechanism of hyperglycaemia on trophoblast cells in vitro was not clearly stated. What do the results of this study add? This is the first study to identify the effect of hyperglycaemia on placentas of gestational diabetes mellitus (GDM) women with macrosomia and normal pre-pregnancy body mass index (BMI), and uncover the molecular mechanism of hyperglycaemia on trophoblast cells in vitro. What are the implications of these findings for clinical practice and/or further research? Understanding placental changes in the environment of abnormal glucose metabolism which can establish the maternal-placental-foetal interface dysfunction as a potential source of adverse pregnancy outcomes is very necessary. Our study found the fasting plasma glucose and placenta are closely related with the development of GDM-induced macrosomia with normal pre-pregnancy BMI. The mechanism may be hyperglycaemia promotes trophoblast cell proliferation via ERK1/2 signalling. It provides scientific evidence for optimising outcomes of GDM women with normal pre-pregnancy BMI, and could be used for the following studies of relationship between placenta and childhood complications

Using the Ratio of Urine Testosterone to Estrone-3-Glucuronide to Identify the Sex of Chinese Giant Salamanders (Andrias davidianus)

Minimally invasive sampling was used to determine the sex of Chinese giant salamanders (Andrias davidianus). Urine samples (n = 25) were collected from 6 adults in the breeding season and from 19 individuals (7 adults and 12 juveniles) in the non-breeding season. The hormone testosterone (T) and estrone-3-glucuronide (E1G) in urine were collected from Chinese giant salamanders (CGSs), and the hormone extracts were analyzed by enzyme immunoassays (EIA). The data demonstrated that the urine T concentration of the male CGSs was significantly higher than that of the females during the breeding season (p < 0.05) and even more pronounced during the non-breeding season (p < 0.01). The urine E1G concentration of the males was less pronounced than that of the females during the breeding season (p < 0.01) and significantly lower during the non-breeding season (p < 0.05). The urine T/E1G values of all the male salamanders were significantly higher than those of the females (p < 0.01) during both the breeding season and the non-breeding season. An interesting pattern was found in this study: the value of urine log10(T/E1G) of the male CGSs was higher than 1, whereas the value for the females was lower than 1, during both the breeding and non-breeding seasons, and in the adult and sub-adult age groups of CGSs. There were 25 salamanders in this study and the accuracy rate reached 100% by using a log10(T/E1G) value of 1. The results of the log10(T/E1G) value provide new insight into the future development of the sex identification of CGSs and also lay the foundation for accurate sex identification in the preparation for artificial release. This is the first study to show that the T/E1G ratio in urinary hormones is reliable for the sex identification of CGSs. Additionally, urinary hormone T/E1G measures are promising sex identification tools for amphibian or monomorphic species and for those whose secondary sex characteristics are visible only during the breeding season

A New Lab for Testing Biofiltration for Advanced Life Support

Bioregenerative systems for removal of gaseous contaminants are desired for long-term space missions to reduce the equivalent system mass of the air cleaning system. This paper describes an innovative design of a new biofiltration test lab for investigating the capability of biofiltration process for removal of ersatz multicomponent gaseous streams representative of spacecraft contaminants released during long- term space travel. The lab setup allows a total of 24 bioreactors to receive identical inlet waste streams at stable contaminant concentrations via use of permeations ovens, needle valves, precision orifices, etc. A unique set of hardware including a Fourier Transform Infrared (FTIR) spectrometer, and a data acquisition and control system using LabVIEW\sT software allows automatic, continuous, and real-time gas monitoring and data collection for the 24 bioreactors. This lab setup allows powerful factorial experimental design. In the initial phase of testing, the bioreactors will be operated in parallel to evaluate their ability to remove a complex mixture of contaminants including ammonia, carbon monoxide, methane, ethylene, acetone, and n- butanol at various operating strategies (e.g., different reactor configurations, packing medium types, gas residence time, and liquid types). Details of the experimental setup are presented herein together with pilot tests conducted to evaluate the lab setup

Enantioselective Toxicity of Tetramethrin to Different Developmental Stages of Zebrafish (<i>Danio rerio</i>)

Chiral pesticides exhibit enantioselective differences in processes such as biological absorption, metabolism, and toxic effects. Organisms have different physiological characteristics at different developmental stages. Therefore, conducting enantiomeric toxicity studies at different developmental stages of organisms can help deepen the understanding of the ecological effects of chiral pesticides. This study focused on trans-tetramethrin (Tet) and investigated the enantioselectivity in bioconcentration, developmental toxicity, estrogenic effects, and immunotoxicity of Tet’s racemate ((±)-Tet) and its two enantiomers ((+)-Tet and (−)-Tet) in three developmental stages of zebrafish: embryos, yolk sac larvae, and juveniles. The results showed that Tet exhibited different enantioselectivity in lethal, bioconcentration, and teratogenic effects on zebrafish at different developmental stages. The LC50 value was (+)-Tet > (±)-Tet > (−)-Tet, with embryos being the most sensitive, followed by juveniles and yolk sac larvae. The enantioselective bioconcentration was (±)-Tet > (+)-Tet > (−)-Tet, and the bioconcentration effect was greater in embryos than that in yolk sac larvae and juveniles. Developmental toxicity indicated that (+)-Tet and (±)-Tet had higher teratogenic effects on yolk sac larvae than on embryos. Tet exhibited different enantioselective effects on the expression of zebrafish estrogen-related genes and innate immune-related genes at different developmental stages. These results will contribute to a more comprehensive assessment of the aquatic toxicity and environmental risks of chiral pesticides

Molecular Cloning of Heat Shock Protein 60 (<i>Sp</i>HSP60) from <i>Schizothorax prenanti</i> and the Gene Expressions of Four <i>Sp</i>HSPs during Lipopolysaccharide (LPS) Infection

Heat shock proteins (HSPs) play a key role in anti-stress and immune processes and are associated with autoimmune diseases. In order to explore the immunological role of HSPs from Schizothorax prenanti (S. prenanti), SpHSP60 was cloned for the first time in this study, and the gene expressions of SpHSP27, SpHSP60, SpHSP70 and SpHSP90 in the hepatopancreas, head kidney, hindgut and spleen were analyzed by quantitative real-time PCR (qPCR) after treatment with lipopolysaccharide (LPS). The open reading frame of the SpHSP60 gene (GenBank accession number ON245159) is 1728 bp. It encodes a protein of 575 amino acids. Its C-terminus is a highly conserved and repeated glycine sequence, which is an important cofactor in ATP binding. Compared with the control group, most of the SpHSPs were significantly upregulated in the tissues examined at 12 or 24 h after LPS challenge. The most abundant expression of SpHSP70 was found in the head kidney at 24 h after LPS injection, followed by SpHSP27 in the spleen at 24 h; both of these SpHSPs displayed strong expression under the LPS stresses, about 20–70 fold more than that of SpHSP60 and SpHSP90. The temporal expression patterns of the four SpHSP genes were different in the four tissues examined. Taken together, the results suggest that SpHSP27, SpHSP60, SpHSP70 and SpHSP90 participate in innate immunity stimulated by LPS, and the response intensity of the SpHSPs was organ-specific, indicating they could provide early warning information against bacterial infection. The findings in our study will contribute to better understanding the biological processes and important roles of SpHSPs involved in defending against pathogenic bacterial challenge

Project 7: Biofiltration for Advanced Life Support --EAC Presentation 2004

47 slides Related Documents:WM1, WM2, WM3, WM