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Phenotypes associated with this allele
Allele Symbol
Allele Name
Allele ID
Mettl3em1Chhe
endonuclease-mediated mutation 1, Chuan He
MGI:6356356
Summary 4 genotypes
Jump to Allelic Composition Genetic Background Genotype ID
cn1
Mettl3em1Chhe/Mettl3em1Chhe
Mettl14em1Chhe/Mettl14em1Chhe
Stra8em1(GFP/cre)Smoc/Stra8+
involves: C57BL/6J MGI:6681853
cn2
Mettl3em1Chhe/Mettl3em1Chhe
Stra8em1(GFP/cre)Smoc/Stra8+
involves: C57BL/6J MGI:6681851
cn3
Mettl3em1Chhe/Mettl3em1Chhe
Mettl14em1Chhe/Mettl14em1Chhe
Tg(Ddx4-cre)1Dcas/0
involves: C57BL/6J * FVB MGI:6681848
cn4
Mettl3em1Chhe/Mettl3em1Chhe
Tg(Ddx4-cre)1Dcas/0
involves: C57BL/6J * FVB MGI:6681844


Genotype
MGI:6681853
cn1
Allelic
Composition
Mettl3em1Chhe/Mettl3em1Chhe
Mettl14em1Chhe/Mettl14em1Chhe
Stra8em1(GFP/cre)Smoc/Stra8+
Genetic
Background
involves: C57BL/6J
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Mettl14em1Chhe mutation (0 available); any Mettl14 mutation (36 available)
Mettl3em1Chhe mutation (0 available); any Mettl3 mutation (39 available)
Stra8em1(GFP/cre)Smoc mutation (0 available); any Stra8 mutation (35 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
reproductive system
• caudal epididymal sperm count is only ~2% of that in control mice
• >80% of caudal epididymal sperm exhibit abnormal heads
• elongated spermatids show abnormal head morphologies at epithelial stages I-VIII
• elongated spermatids show abnormal head morphologies and their number is severely decreased from step 13 to step 16 at epithelial stages I-VIII
• progressive motility of caudal epididymal sperm is severely reduced at 2 months of age
• CASA analysis revealed that total motility of caudal epididymal sperm is severely reduced at 2 months of age, indicating defects in sperm flagella
• seminiferous tubules contain very few mature spermatozoa
• however, no detectable abnormalities are observed in germ cells up to step 12 of elongating spermatids
• adult testes are significantly smaller than those in controls
• adult testis/body weight (%) is significantly lower than that in controls
• spermatid differentiation is blocked in late stages of spermiogenesis
• unexpectedly, male meiosis is normal

cellular
• caudal epididymal sperm count is only ~2% of that in control mice
• >80% of caudal epididymal sperm exhibit abnormal heads
• elongated spermatids show abnormal head morphologies at epithelial stages I-VIII
• elongated spermatids show abnormal head morphologies and their number is severely decreased from step 13 to step 16 at epithelial stages I-VIII
• progressive motility of caudal epididymal sperm is severely reduced at 2 months of age
• CASA analysis revealed that total motility of caudal epididymal sperm is severely reduced at 2 months of age, indicating defects in sperm flagella
• N6-methyladenosine (m6A) levels in spermatids of double knockout mice are significantly lower than those in single Mettl3em1Chhe or Mettl14em1Chhe knockouts
• however, no significant differences in m6A levels are noted between double knockout and single knockout spermatocytes
• spermatids from double mutant mice show impaired translation of haploid-specific genes that are essential for spermiogenesis

homeostasis/metabolism
• spermatids from double mutant mice show impaired translation of haploid-specific genes that are essential for spermiogenesis

endocrine/exocrine glands
• seminiferous tubules contain very few mature spermatozoa
• however, no detectable abnormalities are observed in germ cells up to step 12 of elongating spermatids
• adult testes are significantly smaller than those in controls
• adult testis/body weight (%) is significantly lower than that in controls




Genotype
MGI:6681851
cn2
Allelic
Composition
Mettl3em1Chhe/Mettl3em1Chhe
Stra8em1(GFP/cre)Smoc/Stra8+
Genetic
Background
involves: C57BL/6J
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Mettl3em1Chhe mutation (0 available); any Mettl3 mutation (39 available)
Stra8em1(GFP/cre)Smoc mutation (0 available); any Stra8 mutation (35 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
reproductive system
N
• male mice are fertile and exhibit normal spermatogenesis with no detectable defects in meiosis or spermiogenesis

cellular
• N6-methyladenosine (m6A) levels are reduced by 55-65% in pachytene spermatocytes and by 45% in round spermatids relative to controls




Genotype
MGI:6681848
cn3
Allelic
Composition
Mettl3em1Chhe/Mettl3em1Chhe
Mettl14em1Chhe/Mettl14em1Chhe
Tg(Ddx4-cre)1Dcas/0
Genetic
Background
involves: C57BL/6J * FVB
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Mettl14em1Chhe mutation (0 available); any Mettl14 mutation (36 available)
Mettl3em1Chhe mutation (0 available); any Mettl3 mutation (39 available)
Tg(Ddx4-cre)1Dcas mutation (2 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
reproductive system
• no GFRalpha1+ Asingle (As, early stage undifferentiated spermatogonia) or PLZF+ undifferentiated spermatogonia are detected at 4 weeks
• double knockout mice exhibit progressive loss of spermatogonial stem cells, similar to single Mettl3em1Chhe or Mettl14em1Chhe knockouts

cellular
• no GFRalpha1+ Asingle (As, early stage undifferentiated spermatogonia) or PLZF+ undifferentiated spermatogonia are detected at 4 weeks
• double knockout mice exhibit progressive loss of spermatogonial stem cells, similar to single Mettl3em1Chhe or Mettl14em1Chhe knockouts




Genotype
MGI:6681844
cn4
Allelic
Composition
Mettl3em1Chhe/Mettl3em1Chhe
Tg(Ddx4-cre)1Dcas/0
Genetic
Background
involves: C57BL/6J * FVB
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Mettl3em1Chhe mutation (0 available); any Mettl3 mutation (39 available)
Tg(Ddx4-cre)1Dcas mutation (2 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
reproductive system
• testes show defects in spermatogonial stem cell (SSC) development
• however, testes contain normal numbers of gonocytes at birth
• the number of undifferentiated spermatogonia (PLZF+ cells) is similar to that in controls up to P5 but significantly decreased by P7
• no GFRalpha1+ Asingle (As, early stage undifferentiated spermatogonia) or even PLZF+ undifferentiated spermatogonia are detected at 4 weeks
• however, Aaligned (Aal) spermatogonia (derived from As spermatogonia) remain, indicating that exhaustion of the SSC pool is possibly due to increased SSC proliferation
• little or no difference in apoptosis of PLZF+ spermatogonia is observed at P7
• mice exhibit progressive loss of SSCs, causing germ cell depletion
• at P10, EdU incorporation is significantly increased in GFRalpha1+ Asingle (As) spermatogonia (the most primitive set of spermatogonia), indicating higher proliferation of spermatogonial stem cells (SSCs)
• by 6 weeks of age, the seminiferous tubule epithelium is completely devoid of any germ cells, with only SOX9+ Sertoli cells remaining
• adult testes are smaller than normal
• males are sterile

cellular
• testes show defects in spermatogonial stem cell (SSC) development
• however, testes contain normal numbers of gonocytes at birth
• the number of undifferentiated spermatogonia (PLZF+ cells) is similar to that in controls up to P5 but significantly decreased by P7
• no GFRalpha1+ Asingle (As, early stage undifferentiated spermatogonia) or even PLZF+ undifferentiated spermatogonia are detected at 4 weeks
• however, Aaligned (Aal) spermatogonia (derived from As spermatogonia) remain, indicating that exhaustion of the SSC pool is possibly due to increased SSC proliferation
• little or no difference in apoptosis of PLZF+ spermatogonia is observed at P7
• mice exhibit progressive loss of SSCs, causing germ cell depletion
• N6-methyladenosine (m6A) levels are reduced by ~70% in THY1+ undifferentiated spermatogonia
• at P10, EdU incorporation is significantly increased in GFRalpha1+ Asingle (As) spermatogonia (the most primitive set of spermatogonia), indicating higher proliferation of spermatogonial stem cells (SSCs)
• mRNA m6A depletion dysregulates translation of transcripts that are required for SSC proliferation/differentiation

homeostasis/metabolism
• mRNA m6A depletion dysregulates translation of transcripts that are required for SSC proliferation/differentiation

endocrine/exocrine glands
• by 6 weeks of age, the seminiferous tubule epithelium is completely devoid of any germ cells, with only SOX9+ Sertoli cells remaining
• adult testes are smaller than normal





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last database update
04/23/2024
MGI 6.23
The Jackson Laboratory