Characterization Of Semenogelin Proteins In The Human Retina.

Abstract

Abstract: : Purpose: Semenogelin I and II are the major structural protein components of the semen coagulum. Their function is not fully understood, but several activities have been ascribed to semenogelin or semenogelin–derived peptides, e.g. inhibition of sperm motility and capacitation, activation of sperm hyaluronidase and antibacterial properties. Once thought to be specific to seminal vesicles and seminal plasma, these proteins are now known to be expressed in various non–genital tissues like trachea, gastro–intestinal tract, skeletal muscle and kidney. The presence of peptides of both semenogelin proteins was detected in human RPE lysates subjected to proteomic analysis. In the present study, we further analyzed the expression of these proteins in the retinal cells in vivo and in vitro. Methods: Cryo and paraffin sections of human retina were processed for both immunofluorescence and DAB reaction with an antibody that recognizes both forms of semenogelin proteins. The presence of both proteins was analyzed in retina and RPE total lysates, and in a human RPE cell line (D407). Results: Both proteins were detected by western blot in human RPE and in D407 cell lysates. Immune reaction was detected in the ganglion and in the photoreceptor layer of the retina. Conclusions: Semenogelin I and II are expressed in the human retina. Further studies towards addressing the function of these proteins in the retina are in progress.

Keywords: retina • immunohistochemistry • protein purification and characterization