title: Conservation, sex-biased expression and functional annotation of microRNAs in the gonad of Amur sturgeon (Acipenser schrenckii).
abstract: MicroRNAs (miRNAs) are involved in post-transcriptional gene regulation and have crucial roles in regulating the expression of gametogenesis-related genes in animals. However, the mechanism of sex determination and differentiation in the sturgeon has remained unclear. Identifying miRNAs and characterizing sex-biased miRNA expression is therefore critical for understanding the role of miRNAs during sexual differentiation in sturgeon. In this study, five different tissues from sturgeon before sex differentiation and the gonads were used for miRNA expression profiling. We screened 1037 miRNAs in miRBase 20.0 and an additional 103 sturgeon miRNAs using microarray and real-time PCR. We found that the sequences of 477 miRNAs out of a total of 1140 miRNAs were highly conserved (100%) among different fish species. From a total of 663 non-redundant miRNA probes, 481 miRNAs were detected in the gonads of both sexes. Of the 148 miRNAs that were identified to have sex-biased expression patterns between the testis and the ovary (P<0.01), 21 miRNAs (14.19%) were relatively highly expressed in the testis or the ovary with fold-changes >2. The microarray expression patterns of 13 randomly selected sex-biased miRNAs were validated using real-time PCR. Target gene prediction revealed a significant enrichment of functional groups (88 GO terms) and 18 KEGG pathways (P<0.05) and suggested that there are interactions between sex-biased miRNAs and 25 putative gametogenesis-related targets. Therefore, our miRNA expression analysis in juvenile A. schrenckii establishes a foundation for understanding and further investigating the role of miRNAs in sturgeon sex differentiation.
authors.affiliation: Guangdong Entomological Institute/South China Institute of Endangered Animals, Guangzhou, China; Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangzhou, China; Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangzhou, China.
authors.forename: Xiujuan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Guangdong Entomological Institute/South China Institute of Endangered Animals, Guangzhou, China; Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangzhou, China; Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangzhou, China.
authors.forename: Lihong
authors.initials: L
authors.lastname: Yuan
authors.affiliation: Guangdong Entomological Institute/South China Institute of Endangered Animals, Guangzhou, China; Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangzhou, China; Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangzhou, China.
authors.forename: Linmiao
authors.initials: L
authors.lastname: Li
authors.affiliation: Guangdong Entomological Institute/South China Institute of Endangered Animals, Guangzhou, China; Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangzhou, China; Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangzhou, China.
authors.forename: Haiying
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Guangdong Entomological Institute/South China Institute of Endangered Animals, Guangzhou, China; Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangzhou, China; Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangzhou, China. Electronic address: chenjp@gdei.gd.cn.
authors.forename: Jinping
authors.initials: J
authors.lastname: Chen
mesh_terms: D000818:Animals; D005260:Female; D029941:Fish Proteins / Q000235:genetics*; D005399:Fishes / Q000235:genetics*; D005718:Gametogenesis / Q000235:genetics*; D005786:Gene Expression Regulation; D006066:Gonads / Q000166:cytology / Q000378:metabolism*; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D060888:Real-Time Polymerase Chain Reaction; D012737:Sex Factors
chemical_list: D029941:Fish Proteins; D035683:MicroRNAs
keywords: Acipenser schrenckii; Microarray; Sex-biased expression; microRNA