Harderian SOX9: Molecular characterization and its dimorphic expression in hamster

Area of Science:

• Molecular Biology
• Endocrinology
• Genetics

Background:

• The SOX9 gene is known to promote lipogenesis, the process of lipid synthesis.
• The hamster Harderian gland (HG) is a lipid-synthesizing organ that exhibits sexual dimorphism.
• Understanding SOX9's role in the HG is crucial for elucidating lipid metabolism and sexual differentiation.

Purpose of the Study:

• To identify and characterize SOX9 in the hamster Harderian gland (HG).
• To investigate the tissue distribution and expression patterns of SOX9.
• To explore the potential role of SOX9 in the sexual dimorphism of the HG.

Main Methods:

• Sequencing of the full-length SOX9 cDNA from hamster.
• BLAST analysis for sequence homology with other species.
• Quantitative Polymerase Chain Reaction (qPCR) to assess gene expression levels.

Main Results:

• The hamster SOX9 cDNA sequence was determined, encoding a 507 amino acid protein with an HMG box domain.
• SOX9 showed high sequence identity (97-99%) with mouse, rat, and human orthologs.
• SOX9 was highly expressed in the testis, cerebellum, and hypothalamus, with significantly higher abundance in male HGs compared to females.

Conclusions:

• SOX9 is present and conserved in the hamster HG.
• The sexually dimorphic expression of SOX9 in the HG suggests regulation by sex steroids.
• SOX9 may play a role in regulating lipid secretion in the HG, potentially downstream of FGF or androgen signaling.