Isolation of glycoproteins involved in sperm association during epididymal transit

MONCLUS MA; CABRILLANA ME; BOARELLI PV; VINCENTI AE; FORNÉS MW

Merlo, San Luis

Congreso; Reunión Conjunta de: XXII Reunión Científica Anual de la Sociedad de Biología de Cuyo y II Reunión Científica de la Sociedad Argentina de Microscopía (SAMIC); 2004

Sociedad de Biología de Cuyo

In several mammalian species, during epididymal maturation sperm associate conforming structures with characteristic morphology. In Mouse and Rat, these associations consist in 10-15 sperm joined by their heads. Rosettes appear only when sperm reach the distal segment of the epididymis (Tail). This suggests an environmental influence, probably due to sperm - epididymal secretion interactions. In previous studies we described morphologically and ultrastructurally this phenomenon in these species. We noted that an electrondense material associated sperm heads. Glycoproteins recognized by Concanavalin A (Con A) were involved in the sperm association. Rat Epididymal fluid (EF) isolated from adult males by Epididymal perfusion with PBS was fractionated in a Sephacryl S200 column (gel chromatography) and 4 fractions were obtained. Each one of them was tested by coincubation at 37°C with isolated and motile Rat sperm to recreated in vitro the epididymal sperm association (Rosettes). First observations showed that Fraction 1 and 2 (with highest MW), were able to reassociate motile sperm in vitro.  These Fractions will be further purificate by affinity chromatography (Con A column). These group of proteins (containing a- D- Glucose/Manose residues) retained by Con  A will be tested to check if they retain the sperm associating ability.