About   Help   FAQ
Phenotypes Associated with This Genotype
Genotype
MGI:2679977
Allelic
Composition
Arxtm1Pgr/Y
Genetic
Background
involves: 129/Sv * NMRI
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Arxtm1Pgr mutation (0 available); any Arx mutation (20 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging
• male hemizygotes die at 2 days after birth (P2)

growth/size/body
• although hemizygotes are indistinguishable from wild-type or heterozygous (control) littermates at birth, they exhibit retarded growth within 24 hrs after birth, despite normal feeding

homeostasis/metabolism
• hemizygotes display severe hypoglycemia prior to death
• blood glucose levels are only slightly reduced at P1 but drop sharply shortly before P2
• hemizygotes are dehydrated prior to death

behavior/neurological
• hemizygotes display weakness prior to death

endocrine/exocrine glands
• at P2, hemizygotes show a complete lack of mature glucagon-producing alpha cells, with concomitant increases in beta and delta cell numbers relative to control mice
• in contrast, the average number of pancreatic polypeptide (PP)-producing cells and general pancreas morphology remain intact
• moreover, development of the early glucagon-/insulin-expressing cells remains unaffected and no alteration in the total islet cell number is detectable after birth, indicating that alpha-cell progenitors adopt an alternative beta- or delta-cell fate
• at P2, hemizygotes display a 1.3-fold increase in the number of insulin-producing beta cells relative to control mice
• an increase in insulin-producing beta cell number is already evident at E18.5
• at ~E18, mutant pancreatic delta cells are no longer localized to the mantle zone as in wild-type mice; instead, they appear to be scattered within the islet core
• at P2, hemizygotes display a 2-fold increase in the number of somatostatin-producing delta cells relative to control mice
• an increase in somatostatin-producing delta cell number is already evident at E18.5


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)
Citing These Resources
Funding Information
Warranty Disclaimer, Privacy Notice, Licensing, & Copyright
Send questions and comments to User Support.
last database update
04/23/2024
MGI 6.23
The Jackson Laboratory