Comparative transcriptomic analysis of ovary and testis reveals sex-related genes in roughskin sculpin Trachidermus fasciatus

The mechanisms underlying sex determination and differentiation have long intrigued researchers in the fields of development and evolutionary biology.The roughskin sculpin(Trachidermus fasciatus Heckel),displaying sexual dimorphism,provides an ideal model for studying the mechanisms.However,both genetic and genomic information concerning sex determination and differentiation,such as gonadal transcriptome data in roughskin sculpin,are lacking.Here,we present the first gonadal transcriptomes of roughskin sculpin and identify sex-related genes.We identified 8531 differentially expressed genes(DEGs),among them 4065 were upregulated in the ovary and 4466 upregulated in the testis.Several sex-related gene ontology(GO)terms were enriched in ovary-biased genes,including“binding of sperm to zona pellucida”,“egg coat formation”,“positive regulation of acrosome reaction”,“cell division”,and“cell cycle”,while the GO terms such as“spermatogenesis”,“sperm axoneme assembly”,“cilium assembly”,“cilium movement”,and“cilium movement involved in cell motility”were enriched in testis-biased genes.Moreover,six KEGG pathways were significantly enriched in the ovary,whereas only one was enriched in the testis.Of these DEGs,40 sex-related genes were identified,which including 26 testis-biased genes(such as Dmrtb 1,Gsdf,Sox 9 b,Wnt 4 b,Tcp 11 l 2,and Efhb),and 14 ovary-biased genes(such as Cyp 19 a 1 a,Foxh 1,Foxr 1,Gdf 3,Hsd 17 b 12,and Igf 2 bp 3).This gonadal transcript dataset would broaden our understanding of sex determination and differentiation mechanisms in roughskin sculpin,expand the genomic database,support future studies on sex-related gene functions,and facilitate molecular biology research into roughskin sculpin.

Cloning and Sequence Analysis of Beta-actin Gene Full Length cDNA from Trachidermus fasciatus

[Objective] The purpose of this experiment was to reveal the sequence and characteristics of Trachidermus fasciatus beta-actin gene.[Method] Using total RNA of muscle in T.fasciatus as template,three cDNA fragments of beta-actin gene in T.fasciatus were amplified by RT-PCR,5＇-RACE and 3＇-RACE.[Result] A full-length of 1905 bp beta-actin cDNA sequence in T.fasciatus,which includes a 1128 bp length open reading frame encoding a 375-amino acid peptide,was obtained.Sequence alignment of nucleotide and amino acid sequence revealed that T.fasciatus beta-actin shared high homology with that of Epinephelus coioides,Rachycentron canadum,Chrysophrys auratus and of relatively low homology with mammalian and bird.The phylogenetic analysis showed that T.fasciatus beta-actin had closest relationship with Epinephelus coioides.And RT-PCR analysis suggested that the beta-actin gene expressed in four tissues,i.e.,muscle,liver,intestine and brain.[Conclusion] The full length sequence of beta-actin gene with high conservation in T.fasciatus was obtained for the first time.

Effects of osmotic stress on the expression profiling of aquaporin genes in the roughskin sculpin(Trachidermus fasciatus)

Aquaporins(AQPs)are a family of integral membrane proteins that have been shown to be important for osmoregulation in many vertebrates.To identify potential stress resistance-related aqp genes in salinity adaptation of the roughskin sculpin Trachidermus fasciatus,we investigated the time-course expression dynamics of seven aquaporin genes(aqp1,4,7,8,10,11 and 12)in three osmoregulatory tissues(kidney,gill and intestine)and one metabolic tissue(liver).The fish were subjected to two different acute osmotic treatments(seawater-tofreshwater transfer respectively achieved in 1 h and 24 h,namely,E-acute and acute group).The expression profiling of the seven aqp genes were performed using quantitative real-time PCR(qRT-PCR).At the time of all sampling time points(0 h,12 h,24 h and 48 h),no expression of aqp4 was found in the gill,liver and intestine;no expression of aqp7 was found in the gill and liver.Significant differences of aqp expression were determined in the four target tissues,and the mRNA levels were largely variable among gene members and tissues.Similar patterns of the time-course expression were detected in most of the aqp genes in T.fasciatus between the two acute groups,except that only one gene(aqp12)in the kidney and three genes(aqp7,aqp8 and aqp10)in the intestine revealed different expression patterns.These results suggest that the expression response of aqp genes was similar under osmotic changes with different rates.

热胁迫对松江鲈免疫功能的影响

在水温19~31℃,盐度32‰条件下,探究热胁迫对平均体质量为(1.56±0.81)g,平均体长为(5.53±0.81)cm的松江鲈(Trachidermus fasciatus)子二代幼鱼免疫功能的影响。结果显示:当热胁迫水温达到28℃时,松江鲈幼鱼体内总抗氧化能力、总超氧化物歧化酶及还原型谷胱甘肽的水平出现显著上升;但随着热胁迫水温升高以及养殖时间增加,机体内免疫活性酶无法有效清除体内产生的氧自由基,松江鲈幼鱼免疫酶活性和抗氧化功能会受到显著的抑制,导致松江鲈幼鱼免疫功能下降。同时,因体内存在大量氧自由基,使得机体内的脂质过氧化物水平和炎症因子基因表达量显著性上升,导致机体出现氧化损伤,对松江鲈幼鱼存活造成威胁。