Phenotypes associated with this allele

• Allele Symbol: Itgb1^tm1Mll
• Allele Name: targeted mutation 1, Ulrich Muller
• Allele ID: MGI:2156945
• Summary: 9 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
cn1	Itgb1^tm1Mll/Itgb1^tm1Mll Gt(ROSA)26Sor^tm4(ACTB-tdTomato,-EGFP)Luo/Gt(ROSA)26Sor^+ Tg(Nes-cre/Esr1*)1Kuan/0	involves: 129S1/Sv * 129X1/SvJ * C57BL/6 * FVB	MGI:5467514
cn2	Itgb1^tm1Mll/Itgb1^tm1Mll Emx1^tm1(cre)Krj/Emx1^+	involves: 129S2/SvPas * 129X1/SvJ	MGI:4947982
cn3	Cdkn1a^tm1Tyj/Cdkn1a^tm1Tyj Itgb1^tm1Mll/Itgb1^tm1Mll Tg(Wap-cre)1Gsc/0	involves: 129S2/SvPas * 129X1/SvJ * C57BL/6 * FVB/N	MGI:3706341
cn4	Itgb1^tm1Mll/Itgb1^tm1Mll Wnt3a^tm1(cre)Eag/Wnt3a^+	involves: 129X1/SvJ	MGI:4947983
cn5	Itgb1^tm1Lscd/Itgb1^tm1Mll Tg(Nes-cre)1Kln/0	involves: 129X1/SvJ * C57BL/6 * SJL	MGI:3703619
cn6	Itgb1^tm1Mll/Itgb1^tm1Mll Tg(Nes-cre)1Kln/0	involves: 129X1/SvJ * C57BL/6 * SJL	MGI:3789472
cn7	Itgb1^tm1Mll/Itgb1^tm1Mll Tg(Wap-cre)1Gsc/0	involves: 129X1/SvJ * FVB/N	MGI:3706335
cn8	Itgb1^tm1Mll/Itgb1^tm1Mll Tg(MMTV-cre)7Mul/0 Tg(MMTV-PyVT)634Mul/0	involves: 129X1/SvJ * FVB/N	MGI:3704008
cn9	Itgb1^tm1Mll/Itgb1^tm1Mll Tg(MMTV-cre)7Mul/0	involves: 129X1/SvJ * FVB/N	MGI:3704007

Genotype
MGI:5467514

cn1

• Allelic Composition: Itgb1^tm1Mll/Itgb1^tm1Mll; Gt(ROSA)26Sor^{tm4(ACTB-tdTomato,-EGFP)Luo}/Gt(ROSA)26Sor⁺; Tg(Nes-cre/Esr1*)1Kuan/0
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ * C57BL/6 * FVB

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

nervous system

abnormal cerebellum external granule cell layer morphology ( J:191222 )

• tamoxifen-treated mice exhibit increased number of granule cell precursors in the external granule layer

abnormal Bergmann glial cell morphology ( J:191222 )

• tamoxifen-treated mice exhibit disorganized Bergmann glial scaffolds with loose and wavy glial fibers

• endfeet of Bergmann glial fibers in tamoxifen-treated mice fail to maintain adhesion to the basement membrane unlike in control mice

ectopic cerebellar granule cells ( J:191222 )

• granule cells in tamoxifen-treated mice are trapped in the external granule layer unlike in control mice

abnormal cerebellum fissure morphology ( J:191222 )

• at P19, tamoxifen-treated mice exhibit severely compromised ingression of several fissures compared with control mice

abnormal cerebellum lobule morphology ( J:191222 )

• tamoxifen-treated mice exhibit the same lobule defects as in Ric8^tm1Zhua/Ric8^tm1Zhua Tg(GFAP-cre)25Mes mice

• however, fissural basement membrane is normal

abnormal cerebellar foliation ( J:191222 )

• tamoxifen-treated mice exhibit the same lobule defects as in Ric8^tm1Zhua/Ric8^tm1Zhua Tg(GFAP-cre)25Mes mice

Genotype
MGI:4947982

cn2

• Allelic Composition: Itgb1^tm1Mll/Itgb1^tm1Mll; Emx1^tm1(cre)Krj/Emx1⁺
• Genetic Background: involves: 129S2/SvPas * 129X1/SvJ

nervous system

nervous system phenotype ( J:170581 )

N

abnormal radial glial cell morphology ( J:170581 )

• radial glia processes in the cortical plate are wavy and frequently crisscross unlike in wild-type mice

• radial glia scaffold is disrupted prior to Cajal-Retzius displacement unlike in wild-type mice

• however, mice exhibit normal radial glia density and identity

radial glial endfoot detachment ( J:170581 )

• at E14.5, mice exhibit retraction of radial glia endfeet compared with wild-type mice

• at E15.0, radial glia endfoot retraction is more severe and spreads across the cortex unlike in wild-type mice

abnormal Cajal-Retzius cell morphology ( J:170581 )

• Cajal-Retzius cells are displaced deeper into the cortex than in wild-type mice

cellular

abnormal radial glial cell morphology ( J:170581 )

• radial glia processes in the cortical plate are wavy and frequently crisscross unlike in wild-type mice

• radial glia scaffold is disrupted prior to Cajal-Retzius displacement unlike in wild-type mice

• however, mice exhibit normal radial glia density and identity

radial glial endfoot detachment ( J:170581 )

• at E14.5, mice exhibit retraction of radial glia endfeet compared with wild-type mice

• at E15.0, radial glia endfoot retraction is more severe and spreads across the cortex unlike in wild-type mice

Genotype
MGI:3706341

cn3

• Allelic Composition: Cdkn1a^tm1Tyj/Cdkn1a^tm1Tyj; Itgb1^tm1Mll/Itgb1^tm1Mll; Tg(Wap-cre)1Gsc/0
• Genetic Background: involves: 129S2/SvPas * 129X1/SvJ * C57BL/6 * FVB/N

endocrine/exocrine glands

abnormal mammary gland growth during lactation ( J:99405 )

♀ • mutants show a decrease in cell proliferation in mammary glands compared to wild-type, however they show a significant increase in cell proliferation compared to the conditional Itgb1 mutant glands, which represents a partial, 55%, reversion of the phenotype

integument

abnormal mammary gland growth during lactation ( J:99405 )

♀ • mutants show a decrease in cell proliferation in mammary glands compared to wild-type, however they show a significant increase in cell proliferation compared to the conditional Itgb1 mutant glands, which represents a partial, 55%, reversion of the phenotype

Genotype
MGI:4947983

cn4

• Allelic Composition: Itgb1^tm1Mll/Itgb1^tm1Mll; Wnt3a^tm1(cre)Eag/Wnt3a⁺
• Genetic Background: involves: 129X1/SvJ

nervous system

nervous system phenotype ( J:170581 )

N • at E15.5, mice exhibit normal Caja-Retzius localization and radial glia scaffold

Genotype
MGI:3703619

cn5

• Allelic Composition: Itgb1^tm1Lscd/Itgb1^tm1Mll; Tg(Nes-cre)1Kln/0
• Genetic Background: involves: 129X1/SvJ * C57BL/6 * SJL

mortality/aging

premature death ( J:71122 )

• majority of mutants die prematurely at varying ages during adulthood

neonatal lethality, complete penetrance ( J:71122 )

• a small fraction of mutants die shortly after birth

growth/size/body

postnatal growth retardation ( J:71122 )

• mutants grow more slowly than controls

nervous system

abnormal cortical marginal zone morphology ( J:71122 )

• perturbed cortical marginal zone, where the anchorage of glial endfeet, the remodeling of basement membrane, and the extension of the meningeal cell layer are perturbed

abnormal Cajal-Retzius cell morphology ( J:71122 )

• at E15.5, small gaps in the Cajal-Retzius cell layer are seen; defects get worse with age such that Cajal-Retzius neurons form ectopia within the cortical wall and cell bodies are randomly oriented

abnormal cerebral cortex morphology ( J:71122 )

• cerebral cortical hemispheres are reduced in size and fused at the midline

• the layers of the cerebral cortex have a wavy appearance at E15.5

• cortical neurons invade the marginal zone in some areas and accumulate deep in the cortical wall

• at P2, layers I-IV and sometimes layer V are disrupted

• cell bodies of cortical neurons are less tightly packed within cortical layers

abnormal cerebellum morphology ( J:71122 )

abnormal cerebellum development ( J:71122 )

• a large number of granule cells form ectopia along the fusion lines of adjacent folia and at the cerebellar surface underlying the meninges

abnormal cerebellar foliation ( J:71122 )

• development of cerebellar folia is defective, with mutants exhibiting fusion between adjacent folia

• with age, folia become progressively more distorted with decreased depth of the folia

abnormal cerebellum vermis morphology ( J:71122 )

• the vermis lacks fissures

small cerebellum ( J:71122 )

• reduction in cerebellum size with age

abnormal CNS glial cell morphology ( J:71122 )

• glial fibers in cortical sections between E18.5 and P14 do not develop glial endfeet but terminate at varying positions within the marginal zone close to the meningeal layer

• glial endfeet are absent at the surface of the cerebellum and within the folia, glial fibers occasionally invade the granule cell layer but do not form expanded endfeet at any age

abnormal meninges morphology ( J:71122 )

• the meningeal cell layer does not extend into the developing cerebellar folia and between the cortical hemispheres

• remodeling of the meningeal basement membrane is defective starting at E15.5 and becomes progressively worse such that by P7, extracellular matrix molecules are absent from areas of the brain surface underlying the meninges

vision/eye

abnormal eyelid morphology ( J:71122 )

• mutants exhibit partially closed eyes

behavior/neurological

ataxia ( J:71122 )

Genotype
MGI:3789472

cn6

• Allelic Composition: Itgb1^tm1Mll/Itgb1^tm1Mll; Tg(Nes-cre)1Kln/0
• Genetic Background: involves: 129X1/SvJ * C57BL/6 * SJL

nervous system

abnormal neuronal precursor cell migration ( J:120076 )

• cultured neuroblasts fail to form a chain and migrate as single cells unlike wild-type neuroblasts

• glial tube integrity is perturbed and neuroblasts migrate ectopically into the tissue surrounding the rostral migratory stream

abnormal rostral migratory stream morphology ( J:120076 )

• the rostral migratory stream is less compact than in wild-type mice and cells do not form chains as in wild-type mice

• neuroblasts within the rostral migratory stream are more dispersed than in wild-type mice and only occasionally for contacts with each other

• glial tube integrity is perturbed and neuroblasts migrate ectopically into the surrounding tissue

small olfactory bulb ( J:120076 )

• the olfactory bulb is reduced in size due to a reduction in cell migration from the subventricular zone to the olfactory bulb

cellular

abnormal neuronal precursor cell migration ( J:120076 )

• cultured neuroblasts fail to form a chain and migrate as single cells unlike wild-type neuroblasts

• glial tube integrity is perturbed and neuroblasts migrate ectopically into the tissue surrounding the rostral migratory stream

Genotype
MGI:3706335

cn7

• Allelic Composition: Itgb1^tm1Mll/Itgb1^tm1Mll; Tg(Wap-cre)1Gsc/0
• Genetic Background: involves: 129X1/SvJ * FVB/N

endocrine/exocrine glands

abnormal mammary gland morphology ( J:99405 )

♀ • at lactation day 5, mammary glands have defects in alveolar integrity, with detachment of luminal epithelial cells resulting in an 11-fold increase in luminally shed and bulging cells due to alterations in cell-basement membrane associations

♀ • the defect in alveolar integrity becomes more pronounced during a second lactation

♀ • density of the lobular-alveolar structures is decreased at day 5 of the first, and more strongly, the second lactation

abnormal mammary gland growth during lactation ( J:99405 )

♀ • luminal cell proliferation is reduced in mammary glands at day 5 of lactation

integument

abnormal mammary gland morphology ( J:99405 )

♀ • at lactation day 5, mammary glands have defects in alveolar integrity, with detachment of luminal epithelial cells resulting in an 11-fold increase in luminally shed and bulging cells due to alterations in cell-basement membrane associations

♀ • the defect in alveolar integrity becomes more pronounced during a second lactation

♀ • density of the lobular-alveolar structures is decreased at day 5 of the first, and more strongly, the second lactation

abnormal mammary gland growth during lactation ( J:99405 )

♀ • luminal cell proliferation is reduced in mammary glands at day 5 of lactation

Genotype
MGI:3704008

cn8

• Allelic Composition: Itgb1^tm1Mll/Itgb1^tm1Mll; Tg(MMTV-cre)7Mul/0; Tg(MMTV-PyVT)634Mul/0
• Genetic Background: involves: 129X1/SvJ * FVB/N

neoplasm

decreased mammary gland tumor incidence ( J:92547 )

• mammary tumors are not detected at 10 weeks of age, like they are in control mice expressing Tg(MMTV-PyVT)634Mul

• although palpable mammary tumors are detected after 4 months of age, these tumors are composed of cells which fail to express the cre transgene and thus express Itgb1

integument

decreased mammary gland tumor incidence ( J:92547 )

• mammary tumors are not detected at 10 weeks of age, like they are in control mice expressing Tg(MMTV-PyVT)634Mul

• although palpable mammary tumors are detected after 4 months of age, these tumors are composed of cells which fail to express the cre transgene and thus express Itgb1

endocrine/exocrine glands

decreased mammary gland tumor incidence ( J:92547 )

• mammary tumors are not detected at 10 weeks of age, like they are in control mice expressing Tg(MMTV-PyVT)634Mul

• although palpable mammary tumors are detected after 4 months of age, these tumors are composed of cells which fail to express the cre transgene and thus express Itgb1

Genotype
MGI:3704007

cn9

• Allelic Composition: Itgb1^tm1Mll/Itgb1^tm1Mll; Tg(MMTV-cre)7Mul/0
• Genetic Background: involves: 129X1/SvJ * FVB/N

endocrine/exocrine glands

endocrine/exocrine gland phenotype ( J:92547 )

N • mice with ablation of Itgb1 in the mammary epithelium show normal mammary ductual outgrowth during puberty and are able to lactate and produce viable litters through multiple rounds of pregnancy