RNA-seq reveals temporal differences in the transcriptome response to acute heat stress in the Atlantic salmon (Salmo salar).

Acute heat stress is common in aquaculture and can affect diverse physiological processes in fish; however, different species of fish have various mechanisms for heat stress adaptation. In this study, we profiled the transcriptome responses of the Atlantic salmon (Salmo salar) to heat stress at 23 °C for 6 or 24 h, compared with that of fish at a normal temperature of 13 °C. The liver was selected as the target tissue for this analysis. A total of 243 and 88 genes were differentially expressed after 6 and 24 h of heat stress, respectively. Of these, only 22 were common to both time points, and most of these common genes were molecular chaperones such as heat shock cognate 71 kDa protein and heat shock protein 90-alpha. Genes such as activating transcription factor 6, calreticulin, protein disulfide isomerase A3, and protein kinase R-like endoplasmic reticulum kinase-eukaryotic initiation factor 2-alpha were only up-regulated after 6 h of heat stress; most of these genes are involved in the endoplasmic reticulum stress pathway. Indeed, endoplasmic reticulum stress was identified at 6 h but not at 24 h, suggesting that stress response plays an important role in the adaptation of Atlantic salmon to acute heat stress. Other up-regulated genes at 6 h were related to the insulin and nucleotide oligomerization domain-like receptor signaling pathways, which directly eliminate misfolded proteins and sustain sugar and lipid homeostasis. At 24 h, heat stress influenced the expression of steroid and terpenoid backbone biosynthesis, which may influence the sexual development and differentiation of Atlantic salmon. Overall, our results elucidate the transcriptome mechanisms that contribute to short-term heat tolerance in the liver of Atlantic salmon.

iTRAQ-based quantitative proteomic analysis of embryonic developmental stages in Amur sturgeon, Acipenser schrenckii.

The Amur sturgeon, Acipenser schrenckii, is an important aquaculture species in China with annual production of about 150 thousand tons in 2015. In this study, we investigated the regulatory proteins and pathways affecting embryonic development of Amur sturgeon, by analyzing of the differential proteomes among four embryonic developmental stages using isobaric tags for relative and absolute quantitation (iTRAQ), combined with the analysis of effects of microelements and antioxidants on embryonic development. Seventy-four, 77, and 76 proteins were differentially expressed according to iTRAQ analysis between the fertilized egg and blastula, blastula and neurula, and neurula and heart-beat stages, respectively. GO and KEGG enrichment analyses indicated that Gluconeogenesis, Ribosome and Proteasome were the most enriched pathways, which may promote energy formation, immune system protection and protein synthesis process in A. schrenckii. The measurement of microelements indicated that Mn, Cu and Fe were obtained from their parents or water environment in A. schrenckii, while Zn plays vital roles throughout embryonic development. The dramatically high level of malondialdehyde (MDA) across the embryonic development may be the main reason leading to a low hatching rate in A. schrenckii. This study provides the basis for further proteome analysis of embryonic development in A. schrenckii.

Identification of genes in the hypothalamus-pituitary-gonad axis in the brain of Amur sturgeons (Acipenser schrenckii) by comparative transcriptome analysis in relation to kisspeptin treatment.

Kisspeptin plays an important role in the reproduction and onset of puberty in vertebrates through stimulation of gonadotropin-releasing hormone (GnRH). However, the mechanisms whereby kisspeptin-related genes regulate sexual differentiation in teleosts are poorly understood. We aimed to study the relationship between the hypothalamus-pituitary-gonad (HPG) axis and sexual differentiation in relation to kisspeptin in the sturgeon Acipenser schrenckii. We performed comparative transcriptomic analysis of the brains of sturgeons treated with KISS1-10 during the gonadal sex-differentiation-sensitive period (170-210days post-hatching (dph)) using an Illumina sequencing platform. We also analyzed mRNA expression levels of genes in the HPG axis using real-time quantitative polymerase chain reaction, and measured estradiol-17ß (E2) and testosterone (T) levels in the brain and gonads using radioimmunological methods. A total of 75,960 and 74,907 unigenes were produced from Kisspeptin-treated and physiological saline-treated fish, respectively, among which 47,891 genes were matched to the non-redundant nr database. Potential genes and their functions were identified by GO (32,435), KEGG (37,619), and COG analyses (18,502). A total of 3169 unigenes were differentially expressed between transcriptomes in KISS1-10- and saline-injected fish, including 300 up-regulated and 2869 down-regulated unigenes. Gene expression levels of KISS1, G protein-coupled receptor-54, GnRH, androgen receptor, estrogen receptor, and Cyp19a in the brain and gonad were significantly affected by KISS1-10 treatment. KISS1-10 injection also significantly increased brain levels of E2 and T, compared with controls. These results support important roles for KISS1 in the regulation of the HPG axis, and in sex differentiation and reproduction in the Amur sturgeon.

Complete mitochondrial genome of Acipenser schrenckii (Acipenseriformes, Acipenseridae).

Abstract The complete nucleotide sequence of Acipenser schrenckii mtDNA is 16,592 bp long (Accession No. KC820796). The total mitochondrial genome is consisted of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and 1 control region. The gene organization and arrangement is identical to typical vertebrates.

[Analysis of organochlorine pesticides and pyrethroid pesticides in vegetables by gas chromatography-electron capture detection coupled with solid-phase extraction using multiwalled carbon nanotubes as adsorbent].

A multi-residue analytical method based on solid-phase extraction (SPE) with multiwalled carbon nanotubes (MWCNTs) as adsorbent was developed. The determination of 6 organochlorine pesticides and 7 pyrethroid pesticides in vegetables (including cucumber, cherry tomato, cabbage, lettuce, purple cabbage, leek, shallot and onion) was carried out by gas chromatography-electron capture detection (GC-ECD). The GC-ECD method used two columns (HP-50 and HP-1) and two ECD detectors. The HP-50 column was used for the analysis and the HP-1 column for validation. The clean-up conditions were optimized. The analytes were extracted by acetonitrile, and the extract was cleaned up by the MWCNTs SPE cartridge. The extract was re-dissolved by hexane, eluted with acetone-hexane (7:3, v/v) from the columns. The recoveries were over 70% for the 11 pesticides in the 13 pesticides. The results indicated that the MWCNTs SPE cartridge was efficient for 8 vegetable samples, because it reduced the contamination of the coloring materials to GC-ECD. The experimental results showed the MWCNTs SPE cartridge can adsorb the coloring materials and the eluant was nearly colorless.

[The effect of hyperbaric oxygen therapy to different degree of hearing loss and types of threshold curve in sudden deafness patients].

OBJECTIVE: To investigate the effect of hyperbaric oxygen therapy to different degrees of hearing loss and different types of threshold curve in sudden deafness patients, and establish a personalized therapy, so as to promote clinical effect to sudden deafness. METHOD: One hundred and twenty cases were divided into two groups respectively (each group 60 cases). Drug treatment had been used in group A for two weeks. The patients in group B received drug treatment combined with hyperbaric oxygen therapy for two weeks. According to the different degrees of hearing loss and the types of audiogram in two groups, the statistical analysis to the difference of hyperbaric oxygen therapeutic effect was done. RESULT: The effective rates was statistically different (chi2 = 8.044, P < 0.01) between group A (60.00%, 36/60) and group B (83.33%, 50/60). There was no statistical difference between two treatment program in mild and the profound deafness patients. The statistical difference could been found between moderate and the severe deafness, the value of chi2 and p were 4.969, 5.560 and 0.040, 0.035, respectively. In group A, the statistical difference could only been found between mild and the profound deafness patients (chi2 = 6.739, P < 0.05). In group B, the statistical difference could been found in mild and the profound deafness, the moderate and the profound deafness, the severe and the profound deafness patients. The value of chi2 were 11.500, 15.058,10.221 and P < 0.01 respectively. The effective rates was no statistical difference in two treatment programs in the upsloping audiogram and the profound deafness. The statistical difference could been found between the downsloping and the flat audiogram, with the value of chi2 and p were 5.144 and 5.969, P < 0.05, respectively. In group A, the statistical difference could been found between the ascending and descending audiogram, the ascending and the flat audiogram,the ascending type and the profound deafness. The value of chi2 were 6.188, 7.247, 8.082 and P < 0.05, respectively. No statistical difference could been found among the other types of audiogram. In group B, no statistical difference could been found among all types of audiogram. CONCLUSION: The effect of hyperbaric oxygen therapy varies with degree of hearing loss and audiogram type. Drug treatment combined with HBOT can promote clinical effect for patients in moderate deafness and severe deafness, the descending and flat type of audiogram.