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Phenotypes Associated with This Genotype
Genotype
MGI:6274231
Allelic
Composition
Katnal2m1Anu/Katnal2m1Anu
Genetic
Background
C57BL/6J-Katnal2m1Anu
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Katnal2m1Anu mutation (1 available); any Katnal2 mutation (201 available)
phenotype observed in females
phenotype observed in males
N normal phenotype

Sperm abnormalities in Katnal2m1Anu/Katnal2m1Anu mice

reproductive system
• multinucleated symplasts are frequently observed in the seminiferous epithelium
• rare sperm found within the epididymis show no capacity for motility
• multinucleated symplasts are frequently observed in the seminiferous epithelium
• all of the few sperm found within the epididymis exhibit short or absent tails
• >99% of male germ cells show complete absence of sperm tail growth
• disorganized outer dense fibers are frequently observed within the cytoplasm of retained spermatids, rather than being within the flagellar compartment
• basal bodies fail to attach to the plasma membrane resulting in a complete absence of microtubule extension, and thus axoneme development, in the vast majority of germ cells
• all of the few sperm found within the epididymis exhibit an abnormally formed mitochondrial sheath in their mid-piece
• cauda epididymal sperm frequently lack mitochondrial mid-pieces
• all of the few sperm found within the epididymis exhibit an abnormal sperm head shape
• during spermiation, most elongated spermatids exhibit a detached acrosome, unlike in wild-type controls
• elongating spermatids frequently show abnormal nuclear (club shaped) morphology
• supernumerary centrioles are frequently observed in the cytoplasm of elongating spermatids
• docking of the centriole to the plasma membrane is never observed in spermatids
• however, coupling of the centriole to the nuclear membrane is normal
• elongating spermatids show excessive constriction of the perinuclear ring of the manchette, unlike in wild-type controls
• perinuclear ring fails to migrate distally but continues to constrict in a development-dependent manner, resulting in elongated spermatids with a knobby head morphology
• during late steps of spermatid elongation, manchette microtubules are abnormally long; manchette length is longer in stage X-XII tubules
• most spermatogenic abnormalities arise during spermiogenesis
• testis histology is relatively normal in pre-meiotic and meiotic germ cells
• during late steps of spermatid elongation, manchette microtubules take longer to disassemble and are still present in stage I-II (step 14) tubules, unlike in wild-type controls
• total epididymal sperm content is reduced by 96.5% relative to wild-type controls; however, testis weight, daily sperm output and germ cell apoptosis are normal, indicating a massive failure of spermiation
• retained elongated spermatids are often observed in stage IX seminiferous tubules, unlike in wild-type controls
• although ectoplasmic specializations are formed and removed normally, no tubulobulbar complexes or residual bodies are formed, and spermatids frequently retain large amounts of cytoplasm, unlike in wild-type controls
• when test mated with wild-type females, males are sterile
• however, mating frequency is normal

cellular
• all of the few sperm found within the epididymis exhibit short or absent tails
• >99% of male germ cells show complete absence of sperm tail growth
• disorganized outer dense fibers are frequently observed within the cytoplasm of retained spermatids, rather than being within the flagellar compartment
• basal bodies fail to attach to the plasma membrane resulting in a complete absence of microtubule extension, and thus axoneme development, in the vast majority of germ cells
• all of the few sperm found within the epididymis exhibit an abnormally formed mitochondrial sheath in their mid-piece
• cauda epididymal sperm frequently lack mitochondrial mid-pieces
• all of the few sperm found within the epididymis exhibit an abnormal sperm head shape
• during spermiation, most elongated spermatids exhibit a detached acrosome, unlike in wild-type controls
• elongating spermatids frequently show abnormal nuclear (club shaped) morphology
• supernumerary centrioles are frequently observed in the cytoplasm of elongating spermatids
• docking of the centriole to the plasma membrane is never observed in spermatids
• however, coupling of the centriole to the nuclear membrane is normal
• during late steps of spermatid elongation, manchette microtubules take longer to disassemble and are still present in stage I-II (step 14) tubules, unlike in wild-type controls
• elongating spermatids show excessive constriction of the perinuclear ring of the manchette, unlike in wild-type controls
• perinuclear ring fails to migrate distally but continues to constrict in a development-dependent manner, resulting in elongated spermatids with a knobby head morphology
• during late steps of spermatid elongation, manchette microtubules are abnormally long; manchette length is longer in stage X-XII tubules
• multinucleated symplasts are frequently observed in the seminiferous epithelium
• rare sperm found within the epididymis show no capacity for motility

endocrine/exocrine glands
• multinucleated symplasts are frequently observed in the seminiferous epithelium


Contributing Projects:
Mouse Genome Database (MGD), Gene Expression Database (GXD), Mouse Models of Human Cancer database (MMHCdb) (formerly Mouse Tumor Biology (MTB)), Gene Ontology (GO)
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last database update
12/17/2024
MGI 6.24
The Jackson Laboratory