All Phenotypes Egr2<tm1Pch> MGI Mouse

postnatal lethality, incomplete penetrance ( J:16077 )

• no lethality before E18.5 and mice are born at the expected ratio

• half usually die within the first 48 hours of life

• most are usually dead around the end of the 2nd week of life

decreased body weight ( J:16077 )

• body size at birth is 90% of controls by weight

weight loss ( J:16077 )

• rapid weight loss after the middle of the 2nd week of life

postnatal growth retardation ( J:16077 )

• weight gain in the first two weeks of life is slowed

• by the middle of the 2nd week, body weight is 72% norma

abnormal motor capabilities/coordination/movement ( J:16077 )

• reduced capacity to walk

tremors ( J:16077 , J:21073 )

• develop between 10 and 15 days of age (J:21073)

decreased locomotor activity ( J:16077 )

abnormal neural tube morphology ( J:16077 )

• shortened

abnormal rhombomere morphology ( J:16077 )

• hindbrain segmentation is less obvious or non-existent at E8.5-E10.5

• length of the rhombencephalon between nerve IX and the trigeminal ganglion is reduced

absent rhombomere 3 ( J:39350 )

• complete elimination of r3

decreased rhombomere 3 size ( J:39350 )

• reduced development of r3

absent rhombomere 5 ( J:39350 )

• probable elimination of r5

decreased rhombomere 5 size ( J:39350 )

• reduced development of r5

• all motor neurons arising exclusively in r5 are lost

decreased rhombomere 6 size ( J:39350 )

• r6 reduced at E9.5

abnormal Schwann cell morphology ( J:21073 )

• major components of myelin in Schwann cells associated with the sciatic nerve are reduced

• nucleus morphology is aberrant

• increased Schwann cell morphology but devoid of myelin

abnormal somatic nervous system morphology ( J:16077 )

abnormal cranial ganglia morphology ( J:16077 )

• facial/acoustic ganglia are almost fused with the trigeminal ganglion

• ganglia V, VII/VIII are juxtaposed but not fused

abnormal cranial nerve morphology ( J:16077 )

abnormal abducens nerve morphology ( J:16077 )

• nucleus for the abducens not detected

• abducens nerve not seen

abnormal facial nerve morphology ( J:16077 , J:39350 )

• motor nucleus of the facial nerve is relatively normal but positioned slightly rostrally (J:16077)

• in close proximity to the trigeminal nerve (J:16077)

• motor roots exit brain separate from those of the trigeminal nerve but both enter the second branchial arch together (J:39350)

• distribution of facial neurons overlap in r6 with those of the glossopharyngeal nerve (J:39350)

abnormal glossopharyngeal nerve morphology ( J:16077 , J:39350 )

• in close proximity to the vagus nerve (J:16077)

• distribution of facial neurons overlap in r6 with those of the glossopharyngeal nerve (J:39350)

abnormal trigeminal nerve morphology ( J:16077 , J:39350 )

• in close proximity to the facial nerve (J:16077)

• trigeminal nuclei are normal until E15.5 then dramatically reduced at E16.5 (J:39350)

• presence of trigeminal nucleus is inconsistent at E17.5 and almost completely eliminated by E18.5 (J:39350)

• motor roots exit brain separate from those of the facial nerve but both enter the second branchial arch together (J:39350)

abnormal vagus nerve morphology ( J:16077 )

• in close proximity to the glossopharyngeal nerve

abnormal sciatic nerve morphology ( J:21073 )

• major components of myelin in Schwann cells associated with the sciatic nerve are reduced

abnormal mandible morphology ( J:30822 )

• deformed

abnormal long bone morphology ( J:30822 )

decreased diameter of long bones ( J:30822 )

decreased diameter of radius ( J:30822 )

decreased diameter of femur ( J:30822 )

decreased diameter of tibia ( J:30822 )

decreased length of long bones ( J:30822 )

• about 24% shorter 2 weeks after birth

short radius ( J:30822 )

short femur ( J:30822 )

short tibia ( J:30822 )

abnormal bone structure ( J:30822 )

• bones very porous although bones of the skull are less affected

abnormal skeleton development ( J:30822 )

abnormal long bone epiphyseal plate morphology ( J:30822 )

• lack of contact between growth plate and osteoblasts

decreased width of hypertrophic chondrocyte zone ( J:30822 )

• compressed hypertrophic growth plate

• reduced number and length of calcified trabeculae

abnormal bone mineralization ( J:30822 )

• skeleton deficient in calcium

delayed eyelid opening ( J:16077 )

• retarded