The integration of Expression, Experimental and Ontology information allow us to identify specific effects induced by FSH carbohydrate moiety

LORETI NAZARETH; FRESNO CRISTOBAL; FERNANDEZ ELMER; CAMPO STELLA

Córdoba

Congreso; 2do Congreso Argentino de Bioinformática y Biología Computacional; 2011

Background: Previous studies [1-3] have shown that different physiological conditions in women (menstrual cycle, full lactation, perimenopause and postmenopause) are associated with variations in the degree of syalilation and complexity of FSH oligosaccharides. FSH carbohydrate moiety determines not only the hormone half-life but also the biological response in the target cell [4]. The objective of the present study was to determine the possible differential regulation of granulosa cell gene expression by recombinant human FSH (rhFSH) glycosylation variants. Materials and Methods: Four rhFSH preparations: more acidic, AC; less acidic, BA; those bearing complex, highly branched (UB) and hybrid type (FR) oligosaccharides were used to stimulate a human ovarian steroidogenic granulosa cell line (KGN). Cells were cultured with rhFSH glycosylation variants (20 ng/mL) for 24h. Purified total RNA was hybridized on Affimetrix GeneChip® Human Gene 1.0 ST and Gene Expression and Ontology analysis were performed. A method to incorporate expression and experimental information was designed in order to obtain biologically relevant information. Results: The above mentioned strategy allowed us to find cellular homeostasis, nucleosome organization, steroid binding, steroid dehydrogenase and ion transport enriched by AC. When BA was added, enriched Gene Ontology terms were mainly associated to important aspect of the reproductive process such as gamete generation, cell differentiation (i.e.growth factors) and cell secretion. Programmed cell death as well as cell adhesion and peptide binding were linked to UB. Meanwhile, important aspects of cell endocrine activity such as steroid metabolism, ovarian follicle development, cytoskeleton (i.e. keratin), response to steroid hormones, cytokine receptors were identified in FB cultures. Conclusions: Integration of Gene expression, Experimental Design and Ontologies allowed us to easily identify meaningful biological information. In this case, results led us to recognize differentially regulated genes by rhFSH glycosylation variants. Moreover, it was possible to associate biological process and molecular functions with specific characteristics of FSH carbohydrate moiety. References 1-Creus S, Pellizzari E, Cigorraga S, Campo S (1996) Clinical Endocrinol 44:2, 181-189. 2-Loreti N, Ambao V, Juliato CT, Machado C, Bahamondes L, Campo S. (2009) Clin Endocrinol (Oxf). 71, 558–565. 3-Velasquez EV, Creus S, Trigo RV, Cigorraga SB, Pellizzari EH, Croxatto HB, Campo S. (2006) 3- Hum Reprod. 21(4):916-923. 4-Ulloa-Aguirre A, Cravioto A, Damian-Matsumura P, Jimenez M, Zambrano E, Diaz-Sanchez V. (1992) Hum Reprod. 7(1):23-30.