Title : The human
"prion-like" protein Doppel is expressed in both Sertoli cells and spermatozoa
Abstract :
- The prion-like Doppel protein ( Dpl ) has many biochemical and structural properties in common with the cellular prion protein ( PrP (c)), and the physiological role of neither protein is known
- Experimental data suggest either direct or indirect interaction between the two proteins
- In this study, we investigated the expression pattern and biochemical characteristics of Dpl in human tissues and in Chinese hamster ovary cells transfected with wild-type or variant human Dpl gene constructs
- Human Dpl appears to be a glycosylphosphatidylinositol-anchored glycoprotein with N- and O-linked sugars
- It was found on Sertoli cells in the testis, on the flagella of epididymal and mature spermatozoa, and in seminal plasma
- Dpl coexists only with N-terminally truncated isoforms of PrP (c) on mature spermatozoa
- The localization of human Dpl on both Sertoli cells (somatic cells) and spermatozoa (germinal cells) strongly suggests that this protein may play a major role in human male fertility
- Finally, our data indicate that spermatozoa are thus an interesting model for studies of the potential interaction between Dpl and PrP (c)