바다송사리(Oryzias dancena)로 부터 생식소 전사체 분석을 통한 암수 특이적 발현 유전자 탐색

Abstract

Marine medaka; Oryzias dancena is an important species in coastal areas of Asian distribution which has a potential of being an ideal vertebrate model for biological development and comparative genomic studies. Therewithal, increasing genomic studies feasible with aquaculture, generates a need for further insight especially in sex-related mechanisms such as; gametogenesis, gonadal development and sex determination/differentiation process in these species. However, for this species, the recent studies about the molecular process related with the sex-biased mechanisms has not been yet extensively studied. By using Illumina RNA-Seq technology, high-quality reads from the cDNA libraries of ovary (58,412,985), testis (58,605,939) and muscle (67,583,838), were assembled into 369,054 unigenes with a successfully annotated sequence rate with 16,548 transcripts. Identification of the candidate genes were chosen through this transcriptome database analysis by using published literature database, trimmed mean of M values matrix (TMM) and differentially expressed genes (DEG’s) obtained from transcriptome analysis. Differential expression analysis generated 23,497 differentially expressed genes through the comparison of ovary and testis. Also muscle transcriptome against gonadal transcriptome (ovary-testis) analysis of differential expression was estimated as 29,556 genes in total, which gave us a wide range of potential sex-biased sequence database. Sex biased genes were analyzed and compared through categorizing them as sex-enriched genes, sex-specific genes, gonad-specific genes, TMM and differentially expressed genes in gonadal transcriptome. The aim of this thesis is to generate a comprehensive list of candidate sex-biased genes that are differentially expressed between gonads which will provide a better understanding of tissue-specific genes from both sexes by further investigations for functional studies.