Hsp90b1 knockout targeted to male germline: a mouse model for globozoospermia

To study the role of Hsp90b1, an endoplasmic chaperone, we have built a conditional knockout by crossing Hsp90b1flox/flox with the Vasa-Cre transgenic line. Spermatozoa deficient in Hsp90b1 could not naturally fertilize oocytes and exhibited large and globular heads with abnormal intermediate pieces, a phenotype reminiscent of human globozoospermia.