Search

Antarctic icefish is the only known vertebrate species that lacks oxygen-carrying hemoglobin and functional erythrocytes. To reveal the unique hematopoietic process of icefish, we used an integrated approach including tandem mass tag (TMT) labeling and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to quantify the dynamic changes in the head kidney whole proteome of a white-blooded icefish, Chionodraco hamatus, compared to those in two other red-blooded Antarctic fish, Trematomus bernacchii and Notothenia coriiceps. Of the 4672 identified proteins, in the Antarctic icefish head kidney, 123 proteins were significantly upregulated and 95 proteins were downregulated. The functional grouping of differentially expressed proteins (DEPs) based on KEGG pathway analysis shows that white blood fish and red blood fish have significant differences in erythropoiesis, heme biogenesis, leucocyte and platelet cell development. The proteins involved in the hematopoietic process in icefish showed a clear trend of downregulation of erythroid lineage marker proteins ([beta]-Spectrin, hemoglobin, CTCF and tfr1a) and upregulation of lymphoid and megakaryocytic lineage marker proteins, including CD9, ITGB2, and mTOR, which suggests a shift in hematopoiesis in the icefish head kidney due to the loss of erythrocytes. Moreover, western blotting analysis showed that a significantly down expression level of CTCF protein was detected in the icefish head kidney, which was in line with the proteomics data. The results of the present study not only provide basic datasets for the head kidney proteins of Antarctic fishes, but also provide important references for studies on immunity and hematopoiesis in various species., Author(s): Ruonan Jia [sup.1] , Shaojun Huang [sup.1] , Wanying Zhai [sup.2] , Shouwen Jiang [sup.2] , Wenhao Li [sup.2] , Faxiang Wang [sup.1] , Qianghua Xu [sup.1] [sup.3] [sup.4] [...]

ABSTRACT The swimming crab Portunus trituberculatus is an important fishery and aquaculture species in China, and salinity has a significant effect on its physiological processes. To verify whether the calcyclin-binding [...]

The swimming crab, Portunus trituberculatus, is an important marine fishery and aquaculture species. Although P. trituberculatus is a euryhaline species, water salinity condition influenced its distribution, migration route, and artificial propagations. To investigate gene expression in the P. trituberculatus exposed to different salinity stresses, 2426 expressed sequence tags (ESTs) from gill cDNA library were selected to spot on a cDNA microarray chip. In total, 417 differentially expressed genes were identified and grouped into eight clusters by hierarchical clustering analysis. Approximately 71.5% of grouped genes belonged to three independent expression patterns, indicating that these three expression patterns may represent three important stress tolerance pathways or networks in P. trituberculatus. Moreover, our cDNA microarray data suggested that there were differences in gene expression patterns of P. trituberculatus for low salinity and high salinity acclimation, suggesting that two salinity challenges resulted in a wide variation of gene expression in P. trituberculatus. In addition, a series of genes such as CCAAT/enhancer-binding protein, Na/K ATPase [beta]-subunit, and heat shock proteins (HSPs) genes were suggested to be key elements during salinity acclimation process. Overall, this work represented an important step toward understanding the molecular processes and mechanisms involved in salinity acclimation of the swimming crab., Author(s): Qianghua Xu [sup.1] [sup.2] , Yang Liu [sup.1] [sup.2] Author Affiliations: (1) grid.412514.7, 0000000098332433, The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, College of [...]

The antifreeze glycoprotein-fortified Antarctic notothenioid fishes comprise the predominant fish suborder in the isolated frigid Southern Ocean. Their ecological success undoubtedly entailed evolutionary acquisition of a full suite of cold-stable functions besides antifreeze protection. Prior studies of adaptive changes in these teleost fishes generally examined a single genotype or phenotype. We report here the genome-wide investigations of transcriptional and genomic changes associated with Antarctic notothenioid cold adaptation. We sequenced and characterized 33,560 ESTs from four tissues of the Antarctic notothenioid Dissostichus mawsoni and derived 3,114 nonredundant protein gene families and their expression profiles. Through comparative analyses of same-tissue transcriptome profiles of D. mawsoni and temperate/tropical teleost fishes, we identified 177 notothenioid protein families that were expressed many fold over the latter, indicating cold-related up-regulation. These up-regulated gene families operate in protein biosynthesis, protein folding and degradation, lipid metabolism, antioxidation, antiapoptosis, innate immunity, choriongenesis, and others, all of recognizable functional importance in mitigating stresses in freezing temperatures during notothenioid life histories. We further examined the genomic and evolutionary bases for this expressional up-regulation by comparative genomic hybridization of DNA from four pairs of Antarctic and basal non-Antarctic notothenioids to 10,700 D. mawsoni cDNA probes and discovered significant to astounding (3-to >300-fold, P < 0.05) Antarctic-specific duplications of 118 protein-coding genes, many of which correspond to the up-regulated gene families. Results of our integrative tripartite study strongly suggest that evolution under constant cold has resulted in dramatic genomic expansions of specific protein gene families, augmenting gene expression and gene functions contributing to physiological fitness of Antarctic notothenioids in freezing polar conditions. cold adaptation | comparative genomics | gene duplication | genome evolution | retrotransposon