TITLE:
Sex-Based Variation of Gene Expression in the Gonads and Fins of Russian Sturgeon (Acipenser gueldenstaedtii)
AUTHORS:
Gad Degani, Akram Hajouj, Avshalom Hurvitz
KEYWORDS:
Acipenser, Gene Expression, Sexual Maturation, Gonads, Sex Markers
JOURNAL NAME:
Open Journal of Animal Sciences,
Vol.11 No.1,
January
27,
2021
ABSTRACT: Russian sturgeon (Acipenser
gueldenstaedtii)
is a primitive freshwater fish and a source of black caviar. The genes involved in sexual
determination and differentiation are still unknown and there are no molecular
markers for sex identification in this species. Studying the variation of the
sex-based differences in genomic sequences and in gene expression in the
sturgeon may lead to markers of sex in early stages of development and advances
in aquaculture, as well as provide novel insights about the evolution of
reproduction, sex determination, and sexual differentiation mechanisms in
vertebrates. Previous studies by our and other groups have identified
differentially expressed genes in the gonads of adult female and male sturgeon.
The current study aimed to test whether these genes were also differentially expressed in non-gonadal tissue, namely
fins. We measured by qRT-PCR the mRNA levels of 29 known and novel sex-related
genes in the gonads and fins of males (4 years old) and females (7 years old;
sexual maturation is earlier in males than in females). Six genes (ATP6, IGFRM,
LIA1A, S1A, NPL1A, GAPDH and SOX9) showed higher expression in female fins. However, only ATP6 mRNA levels differed in fins
of males and females of the same age (4 years old). These findings underscore
the impracticality of sex identification based on gene expression in
non-gonadal tissue and the need for genetic sex markers in the Russian
sturgeon.