Phenotypes Associated with This Genotype

Genotype
MGI:2182741

• Allelic Composition: Smad4^tm1Mak/Smad4^tm1Mak
• Genetic Background: either: (involves: 129P2/OlaHsd * C57BL/6J) or (involves: 129P2/OlaHsd * C57BL/6J * CD-1)

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

mortality/aging

embryonic lethality between implantation and somite formation, complete penetrance ( J:45399 )

• die at or before E7.5

• by E8.5, most embryos are in resorption or degenerating within the yolk sac

embryo

abnormal ectoderm development ( J:45399 )

• 35% of embryos at E6.5 show a reduced ectoderm region

abnormal mesoderm development ( J:45399 )

• in vitro differentiation of the mesoderm in ES cells is impaired

failure to gastrulate ( J:45399 )

• due to impaired visceral endoderm function

rostral body truncation ( J:45399 )

• rescue of gastrulation defects by complementation with tetraploid embryonic cells results in chimeric embryos with mesoderm-derived tissue that show impaired anterior development/anterior truncations at E8.5

embryonic growth arrest ( J:45399 )

• development is arrested at the onset of gastrulation

decreased embryo size ( J:45399 )

• at E5.5

abnormal embryonic tissue morphology ( J:45399 )

• at E5.5, the embryonic region is reduced in size

• by E6.5, the embryonic region is reduced and poorly developed but displays a proamniotic cavity

absent mesoderm ( J:45399 )

• no histological signs of mesoderm development at E6.5

• failure to form mesoderm is confirmed by the absence of mesodermal markers

failure of primitive streak formation ( J:45399 )

• at E6.5

abnormal embryonic-extraembryonic boundary morphology ( J:45399 )

• embryos have a poorly defined boundary between the embryonic and the extraembryonic regions

disorganized extraembryonic tissue ( J:45399 )

• extraembryonic region appears disorganized

abnormal visceral endoderm morphology ( J:45399 )

• poorly organized visceral endoderm at E5.5

• visceral endoderm development is abnormal and in vitro differentiation of the visceral endoderm in ES cells is impaired

growth/size/body

decreased embryo size ( J:45399 )

• at E5.5

cellular

decreased cell proliferation ( J:45399 )

• reduced cell proliferation in embryos at E6.5, as shown by BrdU staining