All Phenotypes Best1<tm1Web> MGI Mouse

coiled sperm flagellum ( J:221655 )

• a large fraction of sperm display severe coiling of the flagellum, suggesting impaired sperm volume regulation

detached sperm flagellum ( J:221655 )

• a high percentage of sperm exhibit heads without tails, indicating enhanced decapitation

kinked sperm flagellum ( J:221655 )

• a large fraction of sperm display angulation of the flagellum

necrospermia ( J:221655 )

• 30% decline in cauda sperm viability

abnormal acrosome morphology ( J:221655 )

• increase in the number of acrosome-reacted, -vesiculated, or -thickened acrosomal structures

• the fraction of acrosome intact spermatozoa declines drastically as spermatozoa progress from the caput to the corpus and cauda region of the epididymal duct

absent acrosome ( J:221655 )

• increase in the number of acrosome-reacted (perforated or absent acrosome cap) sperm

reduced male fertility ( J:221655 )

• matings between male homozygotes and wild-type females result in only 7 pups born out of 23 crosses (0.3 pups per mating), whereas wild-type breedings yield an average of 12.1 pups per mating

• Background Sensitivity: male subfertility is less severe on a C57BL/6 background than on a CD-1 background (following at least 10 backcrosses onto the CD-1 strain)

abnormal sperm physiology ( J:221655 )

• caudal sperm show impaired tolerance to changes in osmotic pressure

• however, basal cytosolic Ca²⁺ levels [Ca2+]i, ATP-induced, and swelling-activated increases in [Ca²⁺]i are similar to those in wild-type controls, indicating normal Ca²⁺ homeostasis

asthenozoospermia ( J:221655 )

• severe decrease in all sperm motility parameters analyzed (including curvilinear velocity, average path velocity, straight line velocity, and amplitude of lateral head displacement) relative to wild-type sperm

• partial rescue of total motility in caudal spermatozoa after exposure to solutions with increasing osmolality (THY290, 16 +/- 4%; THY350, 20 +/- 7%; THY420, 31 +/- 6%), although percentage of total motility is significantly lower at all osmotic conditions relative to wild-type controls (22 +/- 8% vs. 65 +/- 7%)