About   Help   FAQ
Phenotypes Associated with This Genotype
Genotype
MGI:2175097
Allelic
Composition
Lamb2tm1Jrs/Lamb2tm1Jrs
Genetic
Background
involves: 129S1/Sv * 129X1/SvJ
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Lamb2tm1Jrs mutation (1 available); any Lamb2 mutation (38 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging

growth/size/body
• after 1 week of age (J:23783)
• grow at a normal rate for 6 days after birth, then cease growing by P8 and do not gain weight from P8 to P14 (J:27732)

nervous system
• reduction in retina thickness is attributable almost entirely to a decrease in photoreceptor length
• inner segments fail to increase in length at 3-4 weeks after birth are about 50% shorter at P25
• outer segments fail to increase in length at 3-4 weeks after birth are about 50% shorter at P25, however they still express rhodopsin
• abnormal rod photoreceptor synapses
• unbranched end plate and absence of junctional folds at neuromuscular synapse
• abnormal Schwann cell processes, absence of active zones and abnormal distribution of synaptic vesicles at neuromuscular synapses
• altered miniature endplate potential frequency

renal/urinary system
• urinary protein increased approximately 100-fold between P2 and P15 (J:23783)
• develop massive proteinuria due to failure of the glomerular filtration barrier (J:27732)
• albumin is the major protein component of the proteinuria
• the foot processes of visceral epithelial cells are frequently fused
• glomeruli form in normal numbers and kidneys appear normal, however the renal glomerular basement membrane occasionally shows thickening and outpocketing
• the glomerular basement membrane remains rich in Lamb1, indicating a compensatory response for lack of Lamb2
• failure of the glomerular filtration barrier

homeostasis/metabolism
• urinary protein increased approximately 100-fold between P2 and P15 (J:23783)
• develop massive proteinuria due to failure of the glomerular filtration barrier (J:27732)
• albumin is the major protein component of the proteinuria

immune system

behavior/neurological
• mutants are lethargic and move about with difficulty

vision/eye
• exhibit about twice the amount of programmed cell death at P15, however still exhibit the basic developmental trend of a decrease in dying cells with age
• outer retina contains aberrant processes in the interphotoreceptor matrix
• reduction in retina thickness is attributable almost entirely to a decrease in photoreceptor length
• inner segments fail to increase in length at 3-4 weeks after birth are about 50% shorter at P25
• outer segments fail to increase in length at 3-4 weeks after birth are about 50% shorter at P25, however they still express rhodopsin
• abnormal rod photoreceptor synapses
• the outer plexiform layer is disrupted as only 7% of observed rod invaginating synapses appear normal, whereas the inner plexiform layer is undisturbed
• the outer plexiform layers rarely contain fully formed triads and instead exhibit a variety of malformations
• tirads and dyads (relatively mature synapses) account for only about 55% of the ribbon synapses
• most conspicuous malformation is floating ribbons, fully assembled ribbon complexes with associated synaptic vesicles that are unapposed to any postsynaptic element
• reduction in thickness of the retina is first noticeable at P13
• abnormal electroretinograms; amplitude of the b-wave and slope of the b-wave intensity-response function are both decreased
• the b-wave is flatter and approaches a linear function, rather than the exponential shape of the control, indicating that photoreceptor to bipolar transmission is not as effective

cellular
• exhibit about twice the amount of programmed cell death at P15, however still exhibit the basic developmental trend of a decrease in dying cells with age

Mouse Models of Human Disease
DO ID OMIM ID(s) Ref(s)
nephrosis DOID:2527 J:27732
Pierson syndrome DOID:0060852 OMIM:609049
J:106005


Contributing Projects:
Mouse Genome Database (MGD), Gene Expression Database (GXD), Mouse Tumor Biology (MTB), Gene Ontology (GO), MouseCyc
Citing These Resources
Funding Information
Warranty Disclaimer & Copyright Notice
Send questions and comments to User Support.
last database update
06/12/2018
MGI 6.12
The Jackson Laboratory