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Review
. 2015 Sep-Oct;17(5):708-10.
doi: 10.4103/1008-682X.156119.

Phosphorylation of Izumo1 and Its Role in Male Infertility

Samantha A M Young, John Aitken, Mark A Baker  1
Affiliations
Review

Phosphorylation of Izumo1 and Its Role in Male Infertility

Samantha A M Young et al. Asian J Androl. 2015 Sep-Oct.

Abstract

Izumo1 is a testis-specific gene product, whose function is essential for sperm-egg fusion. Throughout its lifespan, Izumo1 is posttranslationally modified, being both N-linked glycosylated on its extracellular domain and phosphorylated on the intracellular C-terminal tail. Within the caput regions of the rat epididymis, two phosphorylation events have been documented. However, as sperm pass through the epididymis, this cytoplasmic portion of Izumo1 has been shown to contain up to seven phosphorylation sites. Remarkably, in the rat, in correlation with these events, Izumo1 undergoes sub-cellular re-location, moving from the head/tail regions of the spermatozoa, to a predominantly equatorial segment location once they have reached the caudal end of the epididymis.

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Figures

Figure 1
Figure 1
Phosphorylation of Izumo1 during epididymal transit of spermatozoa. Within the caput region, Izumo1 is phosphorylated on two amino acid residues. After spermatozoa have transited to the cauda epididymidis, Izumo1 has seven phosphorylated residues.
See this image and copyright information in PMC

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