MICRORNA ANALYSIS RELATED TO REPRODUCTIVE HORMONE REGULATION IN MALE GONADS OF NILE TILAPIA (OREOCHROMIS NILOTICUS) FED WITH PAPAYA SEED POWDER

• Main Author: Dherika
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/70929
• Institution: Institut Teknologi Bandung

Papaya seed is a natural component that has the potential to be an agent controlling the reproduction level of Nile tilapia. In a previous study, exposure to papaya seed powder (PSP) caused abnormalities in gonadal tissue, decreased kiss2 gene expression, and increased orexin gene expression in male Nile tilapia. This condition leads to inhibition of gonadal maturation and an increase in growth performance. The research shows that biological processes in the body are regulated by certain genes. The expression of these genes can be regulated by microRNAs (miRNAs), which are known to play a role at the post-transcriptional level. However, the role of miRNAs in regulating gene expression that is affected by PSP as an antifertility agent in male Nile tilapia is not widely known. This study aims to determine the effect of the PSP diet on growth performance and condition of gonad tissue, as well as miRNA expression in relation to genes involved in the regulation of reproductive hormones in the male gonads of Nile tilapia. One hundred Nile tilapia seeds aged 2 months were reared for 84 days. There were two treatment groups: fish given PSP at up to 2 g/kg of commercial feed and fish given commercial feed (the control). Growth performance parameters were observed every 14 days. Gonads and livers were weighed to obtain body index values. Histological preparations of male gonads were carried out to examine tissue conditions. RNA isolation from male gonads was carried out, followed by small RNA sequencing, bioinformatic analysis, and statistical data analysis. The result showed that PSP significantly affected the growth performance of male Nile tilapia on the parameters average body weight, specific growth rate, and feed conversion ratio (P-value < 0.05), but not on the parameters condition factor, survival rate, and body index values (P-value > 0.05). Abnormalities in male gonadal tissue were observed, namely disintegration of the germinal compartment and hypertrophy of the interstitial compartment. A percentage result from measuring the number of spermatocytes in male gonads indicated that the treatments were not significantly affected by this value (P-value > 0.05). Bioinformatics analysis revealed that oni-miR-489 expression decreased significantly while oni-miR-10a/b expression increased significantly (P-value ? 0.05). Oni-miR-489 was detected targeting the pyk2 and erk1 genes in GnRH and MAPK signaling pathways. Oni-miR-10a/b was detected targeting the kiss1r gene in the neuroactive ligand-receptor interaction pathway. Based on the results of the study, exposure to PSP in amounts as high as 2 g/kg of feed can affect growth performance and abnormalities in the gonad tissue, as well as the expression of miRNA in the male gonads of Nile tilapia.