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【Objective】 Glucocorticoid receptor (GR) was involved in various biological processes such as osmoregulation, stress and immune modulation in diverse organisms. Therefore, the analysis of GR expression characteristics was conductive to revealing its function in the anti-stress response of fish.【Method】 In the present study, the cDNA of Acipenser dabryanus GR was cloned from the unigene database by transcriptome sequencing of A. dabryanus. The tissue distribution and expression level during starvation stress were further analyzed. 【Result】 The open reading frame of GR was 2316 bp, encoding 771 amino acids, including the conserved zinc finger domain, ligand binding domain of hormone receptors, and the fish specific 9-aa insertion sequence WRARQNMDG. Results showed that GR was ubiquitously expressed in all tested tissues, and was highly expressed in immune-related tissues such as spleen, liver and gill. Relatively high expression levels of GR were also found in brain and heart. Under starvation conditon, the expression level of hepatic GR increased during fasting period and was significantly higher than that of the control group in 7 days and 14 days post starvation. The peak expression of intestinal GR on day 7 of starvation was significantly higher than that on day 0（P<0.05）. After refeeding, the expression level of GR in liver and intestine returned to the control level. 【Conclusion】 The study indicated that GR participated in the stress response process of resisting hunger stress of A. dabryanus. [ABSTRACT FROM AUTHOR]

【Objective】Insulin-like growth factor system(IGFs) are a group of regulating factors that play an important part in the proliferation and differentiation of cells, immunity and development of the skeletal muscle. Therefore, the analysis of IGF expression is conducive to revealing its functions in the process of fish growth and nutritional regulation.【Method】In this study, we obtained the full length cDNA of IGF-1 and IGF-2 from the unigene database by transcriptome sequencing of Acipenser dabryanus. The tissue distribution and expression level during starvation stress were also analyzed. 【Result】The full length of IGF-1 was 2262 bp which contained 292 bp 5′ untranslated region(UTR), 1841 bp 3′ UTR and 489 bp open reading frame(ORF). The ORF of IGF-1 encoded 163-residue peptide. The full length of IGF-2 was 1821 bp which contained 109 bp 5′UTR, 1052 bp 3′ UTR and 660 bp ORF. The ORF of IGF-2 encoded 220-residue peptide. Phylogenetic analysis showed that the IGF-1 and IGF-2 clustered with other species in genus Acipenser. Tissue expression analysis showed that IGF-1 and IGF-2 were widely expressed in different tissues, and IGF-1 was highly expressed in eye while IGF-2 was mostly detected in liver and gonad. During starvation, the expression level of IGF-1 was increased firstly and then decreased significantly in liver, gut and muscle.【Conclusion】The expression level of IGF-1 was decreased significantly during fasting for 14 days compared to the initial value in all the examed tissues(P<0.05), indicating a positive correlation between nutritional status and IGF-1 mRNA level. Whereas, the expression level of IGF-2 was decreased slightly with no significant change detected(P>0.05) during fasting for 14 days compared to the initial value, inferring a diverse function of IGF-1 and IGF-2 in A. dabryanus. [ABSTRACT FROM AUTHOR]

[Objective] Due to the lack of secondary sexual characteristics, it is very difficult to identify the gender of sturgeon. Thus, screening of sex-specific markers to facilitate gender selective breeding will be of great economic value. [Method] In this study, seven polymorphic microsatellite markers (SSR) in Acipenser dabryanus were developed bv transcriptome sequencing and screening, and the sex-linked markers in A. dabryanus were analyzed. [Result]The expected heterozygosity and Shannon-Wiener index were from 0. 3831 to 0.8607 and 0.6541 to 1.9663, respectively. Together with 91 previous reported SSRs, a total of 106 markers were used to characterize the genotype in 96 adult, 4. dabryanus (48 males and 48 females). Results showed that the distribution difference of two bands of the locus ADX21 between males and females reached 60 %. The ADX21-144 bp and the ADX21-151bp were considered male-dominant and female-dominant band respectively in A. dabryanus, indicating that the marker might locate around the sex-determining regions. [Conclusion] So far, this study presents the largest number of SSRs used to screen the sex-related markers in sturgeons. Our research provides plenty basic data for the further study on the development of sex-linked markers as well as the study of the sex-determination mechanism in sturgeons. [ABSTRACT FROM AUTHOR]