Structurally, all these peptides consist of two polypeptide chains (A and B)
linked by two disulfide bonds.
B chain xxxxxxCxxxxxxxxxxxxCxxxxxxxxx
A chain xxxxxCCxxxCxxxxxxxxCx
'C': conserved cysteine involved in a disulfide bond.
'*': position of the pattern.
As shown in the schematic representation above, they all share a conserved
arrangement of four cysteines in their A chain. The first of these cysteines
is linked by a disulfide bond to the third one and the second and fourth
cysteines are linked by interchain disulfide bonds to cysteines in the B
chain. As a pattern for this family of proteins, we have used the region
which includes the four conserved cysteines in the A chain.
December 2004 / Pattern and text revised.
PROSITE method (with tools and information) covered by this documentation:
Blundell T.L. Humbel R.E.
Hormone families: pancreatic hormones and homologous growth factors.
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