Comparative transcriptome analysis reveals expression signatures of albino Russian sturgeon, Acipenseriformes gueldenstaedtii

Yiwen Gong; Mou Hu; Shijian Xu; Bin Wang; Chunlin Wang; Xidong Mu; Peng Xu; Yanliang Jiang

doi:10.1016/j.margen.2019.02.004

Comparative transcriptome analysis reveals expression signatures of albino Russian sturgeon, Acipenseriformes gueldenstaedtii

Mar Genomics. 2019 Aug:46:1-7. doi: 10.1016/j.margen.2019.02.004. Epub 2019 Mar 6.

Authors

Yiwen Gong¹, Mou Hu², Shijian Xu², Bin Wang², Chunlin Wang³, Xidong Mu⁴, Peng Xu⁵, Yanliang Jiang⁶

Affiliations

¹ Key Laboratory of Aquatic Genomics, Ministry of Agriculture and Rural Affairs, CAFS Key Laboratory of Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing, China.
² Hangzhou Qiandaohu Xunlong Sci-Tech Development Company Limited, Quzhou, China.
³ Key Laboratory of Applied Marine Biotechnology (Ningbo University), Ministry of Education, Ningbo, China.
⁴ Key Laboratory of Tropical & Subtropical Fishery Resource Application and Cultivation, Ministry of Agriculture and Rural Affairs, Guangzhou, China.
⁵ Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen University, Xiamen, China.
⁶ Key Laboratory of Aquatic Genomics, Ministry of Agriculture and Rural Affairs, CAFS Key Laboratory of Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing, China; Hangzhou Qiandaohu Xunlong Sci-Tech Development Company Limited, Quzhou, China; Key Laboratory of Applied Marine Biotechnology (Ningbo University), Ministry of Education, Ningbo, China. Electronic address: jiangyl@cafs.ac.cn.

PMID: 30852186
DOI: 10.1016/j.margen.2019.02.004

Abstract

Albinism is a genetically inherited condition that is caused by a series of genetic abnormalities leading to a reduction in melanin production. Russian sturgeon is one of the most valuable freshwater fish species worldwide, and albino individuals have been found in fish farms. Due to its complicated genome and scarce genome-wide genetic resources, the underlying molecular basis of albinism in Russian sturgeon is unknown. In the present study, we first generated transcriptome profile of Acipenser gueldenstaedtii using pooled tissues, which provided reliable reference sequences for future molecular genetic studies. A total of 369,441 contigs were assembled, corresponding to 32,965 unique genes. A comparative analysis of the transcripts from the skin of albino and wildtype individuals was conducted afterwards. A total of 785 unique genes were differentially expressed, including the upregulation of 385 genes and the downregulation of 400 genes in albino individuals. The expression pattern of 16 selected differentially expressed genes was validated using qRT-PCR. Additional annotation, GO enrichment analysis and gene pathway analysis indicated that the melanogenesis pathway may be interrupted in albinism. Eight potential causative genes that were highly likely to be responsible for sturgeon albinism were identified, including Dct, Tyrp1b, Slc45a2, Ctns, Pmela, Pmelb, Cd63, and Bloc1s3, which were found to be significantly down-regulated in albino Russian sturgeon. Moreover, a sliding window analysis of the ratio of nonsynonymous to synonymous nucleotide substitution rates (Ka/Ks) ratios indicated that seven out of the eight genes underwent positive selection during evolution. Our results provide a valuable basis for understanding the molecular mechanism of albinism in fish species and will facilitate future genetic selection and breeding of sturgeon with market-favored traits in aquaculture.

Keywords: Albino; Comparative transcriptome; Melanogenesis; Russian sturgeon.

MeSH terms

Albinism / genetics
Albinism / veterinary*
Animals
Breeding
Fishes / genetics*
Gene Expression Profiling
Gene Expression Regulation
Genomics
Transcriptome*