All Phenotypes Tex46<em1Ncvc> MGI Mouse

• at the sperm head-tail junction, a distinct bend in the head toward the flagella is seen in many cauda epididymal spermatozoa

• testicular spermatozoa have less than 2% of bent heads, while cauda epididymal sperm have about 70% bent heads

abnormal sperm head morphology ( J:355678 )

• all sperm heads lack a distinct hood shape and have a blunted head tip

abnormal acrosome morphology ( J:355678 )

• in a few spermatozoa, the rostral tip of the acrosome blebs out towards the front

• in other spermatozoa, the acrosome cap does not form a tight bond between the structures and blebs out the sides

• however, sperm show normal acrosome reaction

detached acrosome ( J:355678 )

• sperm heads have a distinct space between the acrosomal cap and nucleus

asthenozoospermia ( J:355678 )

• spermatozoa exhibit decreased average path velocity, straight-line velocity, and curvilinear velocity, with overall motility reduced at both 10 min and 2 hours in capacitating medium

• about 50% of spermatozoa are immotile when analyzed in vitro

• however, no abnormalities in sperm flagella are seen

small testis ( J:355678 )

decreased testis weight ( J:355678 )

male infertility ( J:355678 )

• males are infertile despite the formation of copulary plugs

• spermatozoa are unable to fertilize cumulus-intact and cumulus-free zona pellucida-intact intact oocytes in vitro

impaired sperm penetration of zona pellucida ( J:355678 )

• about 37.8% of spermatozoa are able to fuse with zona pellucida-free oocytes in vitro spermatozoa can bind to the zona pellucida in vitro, although at a reduced capacity compared to wild-type but nearly all spermatozoa fail to penetrate through the zona pellucida of destabilized zona pellucida oocytes, indicating that spermatozoa cannot penetrate the zona pellucida but are able to fuse with oocytes