Phenotype Image Detail

Image

Caption

A: Gross appearance to two E11.5 littermates showing a Runx1^tm1Spe/Runx1^tm1Spe embryo (left) with a ventral metencephalic hemorrhagic area (arrowhead) roughly located at the level of the VII-VIII cranial nerve complex and close to the otic placode (arrowhead). (Right) Unaffected Runx1^tm1Spe/Runx1⁺ embryo. B: Gross appearance of an E11.5 Runx1^tm1Spe/Runx1^tm1Spe embryo with several hemorrhagic lesions, including intraventricular (lateral, 3rd, infundibulum, aqueduct, and 4th ventricle), and segmental bleeds in various regions: at the VII-VIII cranial nerve complex (1), cervical (2), thoracic (3), and caudal (4) regions. C: Cross section of the central nervous system (CNS) isthmus of an E11.0 homozygous mutant embryo showing extensive CNS hemorrhages (B) and bilateral symmetrical areas of vascular necrosis (N). There is also blood in the ventricle (*). D: Detail of the same isthmus from a margin of the hemorrhage in C, showing several separate lineal and ventricle hemorrohages (arrowheads), paralleling the location and distribution of the CNS perforating vessels. Also shown is intraventricular blood (*). E: Detail of the CNS/nerve interface of the VII-VIII cranial nerve complex of an E10.5 mutant embryo showing extensive necrosis (N) involving neural crest and endothelial cells. Note a few cells in mitosis (arrowheads), indicating the great cellular activity of these CNS/nerve interfaces. This corresponds to the area of bleeding shown at E11.5 (A, arrowhead; B, 1). Also shown is the edge of the otic (O) placode. F: Detail of the somitic (S) intersomitic necrosis (N) around and probably incloving segmental vessels (c) in an E10.5 mutant embryo. (See B, areas 2-4.) G & H: details of cytospin prepreations from E10.5 yolk sacs showing blood percursor cells and nucleated primitive erythrocytes from wild type and mutant embryos. I & J: Detail of liver sections showing many blood percursor cells in the liver sinusoids (S) of an E11.0 wild type embryo and their absence in the liver sinusoids (S) of the mutant embryo, which essentially contains only circulating nucleated primitive erythrocytes. Arrowheads in I point to examples of nucleated primitive erythroid cells; remaining cells in the sinusoids of wild type livers are less differentiated hematopoietic cells.

Copyright

This image is from Wang Q, Proc Natl Acad Sci U S A 1996 Apr 16;93(8):3444-9. Copyright 1996 National Academy of Sciences, U.S.A. J:35115

Associated Alleles

Symbol	Name
Runx1^tm1Spe	runt related transcription factor 1; targeted mutation 1, Nancy A Speck

Associated Genotypes

Allelic Composition	Genetic Background
Runx1^tm1Spe/Runx1^tm1Spe	either: (involves: 129S4/SvJae * BALB/c) or (involves: 129S4/SvJae * C57BL/6)