Molecular Cloning and Gene Expression Analysis of the Leptin Receptor in the Chinese Mitten Crab Eriocheir sinensis

Background: Leptin is an adipocyte-derived hormone with multiple functions that regulates energy homeostasis and reproductive functions. Increased knowledge of leptin receptor function will enhance our understanding of the physiological roles of leptin in animals. Methodology/Principal Findings: In the present study, a full-length leptin receptor (lepr) cDNA, consisting of 1,353 nucleotides, was cloned from Chinese mitten crab (Eriocheir sinensis) using rapid amplification of cDNA ends (RACE) following the identification of a single expressed sequence tag (EST) clone in a cDNA library. The lepr cDNA consisted of a 22-nucleotide 59-untranslated region (59 UTR), a 402-nucleotide open reading frame (ORF) and a 929-nucleotide 39 UTR. Multiple sequence alignments revealed that Chinese mitten crab lepr shared a conserved vacuolar protein sorting 55 (Vps55) domain with other species. Chinese mitten crab lepr expression was determined in various tissues and at three different reproductive stages using quantitative real-time RT-PCR. Lepr expression was highest in the intestine, thoracic ganglia, gonad, and accessory gonad, moderate in hepatopancreas and cranial ganglia, and low in muscle, gill, heart, haemocytes, and stomach. Furthermore, lepr expression was significantly higher in the intestine, gonad and thoracic ganglia in immature crabs relative to precocious and mature crabs. In contrast, lepr expression was significantly lower in the hepatopancreas of immature crabs relative to mature crabs

Deep-Buried Triassic Oil-Source Correlation in the Central Junggar Basin, NW China

Whether there is an effective deep-buried lacustrine Triassic petroleum system in the Junggar Basin, NW China, has been enigmatic and debated for a long time. Here we conduct an oil-source correlation to address this issue. Results show that the extracted bitumens from the Triassic mudstones in the central basin have distinctive stable carbon isotope and biomarker compositions compared to the Permian-sourced and Jurassic-sourced hydrocarbons, the other two recognized sources in the study area. These characteristics include δ13C value of -30.46~-26.30‰, β-carotane/maximum n-alkane of 0.22–0.41, Pr/Ph of 1.00–1.51, C24 tetracyclic terpane/C26 tricyclic terpane of 0.43–0.96, Ts/Tm of 0.34–0.64, gammacerane/C30 hopane of 0.10–0.14, and regular steranes C27 > C28 < C29 with C29 sterane in dominance (40–50%). These suggest that the Triassic mudstones in the study area host fresh lacustrine organic matters with high input of higher plants. The Triassic-reservoired crude oils and extracts can be divided into two types. Through oil-source correlation, we infer that both type A and type B oils are derived from mixed Permian and Triassic source rocks. Linear regression analysis shows that the contribution from Triassic mudstones to type A and B oils is 67% and 31%, respectively. This implies that the deep-buried Triassic lacustrine mudstones in the Junggar Basin may have some oil-generation potential and thus might represent a new case of Triassic petroleum systems in China and deserves a more detailed and thorough study in future exploration and exploitation

Degradation of Host Proteins and Apoptosis Induced by Foot-and-Mouth Disease Virus 3C Protease

Foot-and-mouth disease (FMD), induced by the foot-and-mouth disease virus (FMDV), is a highly contagious disease of cloven-hoofed animals. Previous studies have reported that FMDV 3C protease could degrade multiple host proteins; however, the degradation mechanism mediated by FMDV 3C is still unclear. Here, we found that transient expression of FMDV 3C degraded various molecules in NF-&kappa;B signaling in a dose-dependent manner, and the proteolytic activity of FMDV 3C is important for inducing degradation. Additionally, 3C-overexpression was associated with the induction of apoptosis. In this study, we showed that an apoptosis inhibitor CrmA abolished the ability of 3C to degrade molecules in NF-&kappa;B signaling. Further experiments using specific caspase inhibitors confirmed the irrelevance of caspase3, caspase8, and caspase9 activity for degradation induced by 3C. Altogether, these results suggest that FMDV 3C induces the widespread degradation of host proteins through its proteolytic activity and that the apoptosis pathway might be an important strategy to mediate this process. Further exploration of the relationship between apoptosis and degradation induced by 3C could provide novel insights into the pathogenic mechanisms of FMDV

Molecular and carbon isotopic geochemistry of crude oils and extracts from Permian source rocks in the northwestern and central Junggar Basin, China

The Junggar Basin is a major oil producing province in China. Most oil reservoirs found so far in this basin are in the Mahu sag and neighboring uplifts, northwestern Junggar Basin. A total of 78 oils and 10 Permian source rocks from the northwestern and central Junggar Basin and two oils and two Permian source rocks from the eastern Junggar Basin were analyzed by GC, GC-MS and GC-IRMS. The 78 oils can be clearly classified into two groups based on these analytical results. For group I oils, delta C-13 values of individual n-alkanes are relatively higher and remain stable with increasing carbon number. For group II oils, these values are relatively lower and decrease at first, and then increase with carbon number. Differences in molecular parameters can be also observed between these two groups of oils. Group I oils generally have: (1) higher Pr/n-C17 and Ph/n-C18 ratios and lower Pr/Ph ratio, and (2) higher gammacerane/( C-30 hopane + gammacerane) and beta-carotane/(beta-carotane + C30 hopane) ratios, compared with group II oils. In addition, group I oils mainly have tricyclic terpane distribution patterns with either C-20 C-21 > C-23 while group II oils mainly have the pattern of C-20 C-23. However, molecular parameters overlap to some extent between these two groups of oils. Group I oils correlate well with the nine source rocks of the Lower Permian Fengcheng Formation (P-1f), while group II oils correlate well with the three source rocks of Middle Permian age based on carbon isotopic and molecular compositions. The occurrence of these two groups of oils in the northwestern and central Junggar Basin are consistent with facies and thickness variations in the source rocks within the Lower Permian Fengcheng Formation (P-1f) and Middle Permian Lower Wuerhe Formation (P-2w). (C) 2017 Elsevier Ltd. All rights reserved

Metabolomics and Physiological Methods Revealed the Effects of Drought Stress on the Quality of Broomcorn Millet during the Flowering Stage

The flowering stage is a critical period for water sensitivity and quality formation of broomcorn millets. However, the effects and mechanisms of drought stress on the quality formation of broomcorn millets are not clear. We used the drought-resistant variety Hequ red millet (H) and the drought-sensitive variety Yanshu No. 10 (Y) were used as materials for drought stress treatment during the flowering stage, metabolomics and physiological methods were used to study the differences in protein, starch, amino acids, medium and medium-long chain fatty acids, and their response characteristics to drought in broomcorn millet. The results showed that different genotypes of broomcorn millets exhibited different response mechanisms in the face of drought stress. In Hequ red millet, drought stress significantly increased the contents of amylopectin (2.57%), pyridoxine (31.89%), and anthocyanin, and significantly decreased the contents of water-soluble protein (5.82%), glutelin (10.07%), thiamine (14.95%) and nicotinamide (23.01%). In Yanshu No. 10, drought significantly decreased amylose by 6.05%, and significantly increased riboflavin and nicotinamide contents by 21.11% and 32.59%. Correlation analysis showed that total starch and amylose were highly significantly positively correlated with methyl palmitate; negatively correlated with amylopectin, vitamins, proteins, free amino acids, and medium-long chain fatty acids; and amylopectin was significantly positively correlated with water-soluble protein, riboflavin, and pyridoxine. Water-soluble protein and glutelin were significantly positively correlated with most free amino acids, medium-long chain fatty acids, and nicotinamide. Thiamine showed significant positive correlation with nicotinamide and significant negative correlation with pyridoxine. Riboflavin was significantly positively correlated with nicotinamide, pyridoxine, and water-soluble protein, and pyridoxine was significantly positively correlated with water-soluble protein. Hequ red millet transforms into amylopectin by consuming water-soluble protein and glutelin, and improves drought resistance by accumulating pyridoxine, and changes its physicochemical properties by decreasing the content of amylose and protein and elevating the content of amylopectin. Yanshu No. 10 resisted drought by catabolizing lipids to produce fatty acids and by consuming amylose for conversion into other metabolites. The present study helps to understand the response of the nutritional quality of millets to drought stress at the flowering stage and provides a theoretical basis for the selection and breeding of superior varieties of millets and drought resistance research

Phylogenetic tree of <i>lepr</i> amino acid sequences in four vertebrates and 22 invertebrates using the neighbour-joining method.

<p>The numbers in the phylogram nodes indicate percent bootstrap support for the phylogeny. The bar at the bottom indicates 5% amino acid divergence in sequences.</p

<i>Lepr</i> mRNA expression levels in six tissues from normal crabs (in the rapid developmental stage), precocious crabs and normal mature crabs.

<p>Values are shown as mean ± S.E. (n = 3). Significant differences relative to intestine are indicated with one asterisk (P<0.05) or with two asterisks (P<0.01).</p

Nucleotide sequence and deduced amino acid sequence of Chinese mitten crab <i>lepr</i>.

<p>Nucleotides (upper) are numbered beginning at the 5′ end. Amino acids (lower), shown using one-letter abbreviations, are numbered beginning at the initiating methionine. The signal peptide is underlined, and the mature peptide is enclosed in the black box. The three conserved cysteine residues in the deduced amino acid sequence are shown in grey boxes. The stop codon is marked by an asterisk. The polyadenylation signal (AATAAA) is enclosed in the black ellipse. Arrows indicate the positions of primers; black boxes indicate the coding region; white lines indicate 5′ and 3′ UTRs; curly bracket indicate position of the EST clone. The <i>E. sinensis lepr</i> sequence was submitted to GenBank under accession number GU443952.</p