Phenotypes for Myl7 MGI:2683464 MGI Mouse

embryonic lethality during organogenesis, complete penetrance ( J:87043 )

• all homozygotes die between E10.5 and E11.5 of cardiovascular insufficiency resulting from atrial malfunction

abnormal intersomitic vessel morphology ( J:87043 )

• by somite pair 24, mutant intersegmental vessels appear disorganized

abnormal vasculogenesis ( J:87043 )

• homozygotes display defects in both extraembryonic and intraembryonic vasculature

• by somite pair 24, mutant cranial vessels are less complex and intersegmental vessels appear disorganized

absent vitelline blood vessels ( J:87043 )

• at E10.0, mutant yolk sacs show absence of both large and small vessels

abnormal myocardial fiber morphology ( J:87043 )

• mutant atrial cardiomyocytes show myofibrillar disorganization, with loss of a normal parallel alignment of thick and thin filaments

• in contrast, cardiomyocytes from the left ventricle display a normal parallel alignment of thick and thin filaments and normal Z-line formation

ventricle myocardium hypoplasia ( J:87043 )

• at E10.0-E10.5, homozygtes exhibit a relatively thin walled ventricular myocardium

trabecula carnea hypoplasia ( J:87043 )

• at E10.0-E10.5, homozygotes underdeveloped ventricular trabeculae

abnormal cardiac epithelial to mesenchymal transition ( J:87043 )

• at E10.0-E10.5, mutant atrioventricular cushions fail to become seeded by mesenchymal cells

abnormal cardiac outflow tract development ( J:87043 )

• by somite pair 24-28, homozygotes display enlarged outflow tracts

abnormal atrioventricular cushion morphology ( J:87043 )

• at E10.0-E10.5, mutant atrioventricular cushions fail to grow, suggesting defective septation and valve formation

abnormal heart looping ( J:87043 )

• homozygotes display abnormal looping architecture with alterations in the length, shape and size of each cardiac segment, and their geometrical relationship to each other

abnormal heart tube morphology ( J:87043 )

• at E8.5 (early linear heart tube stage), homozygotes display enlarged and amorphous hearts, with no clear distinction between the bulbus arteriosus and prospective left ventricle

increased heart atrium size ( J:87043 )

• by somite pair 22, homozygotes exhibit enlarged atria

dilated heart left ventricle ( J:87043 )

• at E10.0-E10.5, homozygotes exhibit a dilated left ventricle

pericardial edema ( J:87043 )

• at E10.5, homozygotes display severe chest edema, indicating heart failure

abnormal heart rate ( J:87043 )

• at E9.5, homozygotes exhibit severely reduced atrial beating (44 bpm) relative to wild-type embryos (516 bpm)

• in contrast, ventricular beating remains relatively unaffected (5310 and 487 for wild-type and mutant ventricles, respectively)

absent vitelline blood vessels ( J:87043 )

• at E10.0, mutant yolk sacs show absence of both large and small vessels

embryonic growth arrest ( J:87043 )

• all homozygotes exhibit growth arrest at approximately somite pair 24-28

embryonic growth retardation ( J:87043 )

• all homozygotes first exhibit growth retardation at ~E9.0-E9.25 (i.e. 15-17 somite pairs)

abnormal visceral yolk sac morphology ( J:87043 )

• at E10.0, mutant yolk sacs display separation of the mesodermal and endodermal layers

abnormal vitelline vascular remodeling ( J:87043 )

• the initial vascular plexus of mutant yolk sacs forms but fails to remodel into a vascular network of larger vessels