E-Locus - Institutional Repository of the University of Crete

Home Search

Results - Details

Search command : Author="Μυλωνάς" And Author="Κωνσταντίνος"

Current Record: 5 of 10

[Add to Basket]

Identifier

000426434

Title

Ιστολογικές και μοριακές πτυχές της φυλετικής διαφοροποίησης στο μαγιάτικο (Seriola dumerili)

Alternative Title

Histological and molecular aspects of sex differentiation in greater amberjack (Seriola dumerili)

Author

Πουλή, Μαρίνα Γ.

Thesis advisor

Παυλίδης, Μιχαήλ

Reviewer

Μυλωνάς, Κωνσταντίνος
Σαρροπούλου, Έλενα

Abstract

The greater amberjack (Seriola dumerili) is one of the promising cultured fish species in the Mediterranean. Characterized by good flesh quality, fast growth rates and high demand in the market, the understanding of its reproduction system is imperative for successful culture. The aim of the present study was the study of sex differentiation in hatchery-produced greater amberjacks, in combination with body growth, as well as of the gonadal microRNA expression, according to gonadal development stage. For this purpose, greater amberjacks’ gonads were collected about every 50 days, from 101 to 408 days post hatching (dph) for histological analysis. They were observed with a light microscope, where they were considered differentiated with the appearance of oocytes or spermatocytes. Concerning the molecular study, gonads of both reproductively immature, one year old, and reproductively capable, four years old, individuals were used. Sex differentiation was smoothly completed and initiated relatively early, with the appearance of males at 101 dph and females at 150 dph. The percentage of differentiated individuals was increasing with time until the completion of differentiation at 408 dph. From the sex ratio that was approaching 1:1, it could be inferred that the culture was not influencing sex differentiation. Concerning body growth, it is possible that the low temperatures during the winter months led to the observed decrease. In the molecular study, miRNA libraries of 12.7 million reads were generated by using Next Generation Sequencing technology. A total of 68 and 31 miRNAs were annotated in the females and males respectively. miRNA differential expression in the gonads was observed between reproductively capable and reproductively immature individuals. Following bibliographic research, possible gonadal functions of the miRNAs were proposed, such as regulation concerning sex differentiation, gametogenesis, cell cycle, immune system, carcinogenesis and body growth.

Language

Greek

Subject

Histology

MicroRNA

Next Generation Sequencing (NGS)

Αλληλούχιση Νέας Γενιάς

Ιστολογία

Φυλετική διαφοροποίηση

Issue date

2019-11-29

Collection