Table 1.

Summary of the effects of angpts and Tie receptor deficiencies in mice.

Tie-1	Tie-2
Single knockout
Died around E18.5.	Died around E10.5.
Reduction in EC structural integrity [22].	Defects in vasculogenesis. Critical for the survival and proliferation of ECs but not their initial formation [21,22].
Double knockout
Abnormal vessel structure during embryogenesis [22].
Angpt 1	Angpt 2
Single knockout
Angiogenic defects reminiscent of those seen in the Tie-2 deficient mice embryos [9].	Required for angiogenesis and lymphatic patterning. Dependent on the genetic background of the mice [23].