PROSITE: PDOC00021 (documentation)
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* EGF-like domain signatures     *
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A sequence of  about thirty  to forty amino-acid  residues  long found in  the sequence of  epidermal  growth  factor  (EGF)  has been  shown  [1 to 6] to be present, in  a more or less conserved form, in a large number of other, mostly animal proteins. The proteins currently known to contain one or more copies of an EGF-like pattern are listed below.

 - Bone morphogenic protein 1 (BMP-1), a  protein which induces cartilage  and bone formation.
 - Caenorhabditis elegans developmental proteins lin-12 (13 copies)  and glp-1  (10 copies).
 - Calcium-dependent serine proteinase (CASP) which degrades the extracellular matrix proteins type I and IV collagen and fibronectin (1 copy). 
 - Cell surface antigen 114/A10 (3 copies).
 - Cell surface glycoprotein complex transmembrane subunit .
 - Coagulation associated proteins C, Z (2 copies) and S (4 copies).
 - Coagulation factors VII, IX, X and XII (2 copies).
 - Complement C1r/C1s components (1 copy). 
 - Complement-activating component of Ra-reactive factor (RARF) (1 copy).
 - Complement components C6, C7, C8 alpha and beta chains, and C9 (1 copy).
 - Epidermal growth factor precursor (7-9 copies).

                 +-------------------+        +-------------------------+
                 |                   |        |                         |
  x(4)-C-x(0,48)-C-x(3,12)-C-x(1,70)-C-x(1,6)-C-x(2)-G-a-x(0,21)-G-x(2)-C-x
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       +-------------------+

'C': conserved cysteine involved in a disulfide bond.
'G': often conserved glycine
'a': often conserved aromatic amino acid
'*': position of both patterns.
'x': any residue
-Consensus pattern: C-x-C-x(5)-G-x(2)-C
                    [The 3 C's are involved in disulfide bonds]
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