{PDOC00234}
{PS00261; GLYCO_HORMONE_BETA_1}
{PS00689; GLYCO_HORMONE_BETA_2}
{BEGIN}
***********************************************
* Glycoprotein hormones beta chain signatures *
***********************************************

Glycoprotein hormones [1,2] (or gonadotropins) are a family of proteins  which
include the mammalian  hormones follitropin (FSH), lutropin (LSH), thyrotropin
(TSH) and chorionic  gonadotropin (CG), as  well as at least two forms of fish
gonadotropins. All these  hormones  consist of two  glycosylated chains (alpha
and beta). In mammalian  gonadotropins,  the  alpha chain  is identical in the
four types of hormones but the beta chains, while homologous, are different.

The beta chains are proteins  of  about  100  to 140 amino acid residues which
contain twelve  conserved  cysteines  all  involved in disulfide bonds [3], as
shown in the following schematic representation.

      +----------------------+
      |         +------------|-----------------------------+
      |       +-|------------|--------+                    |
      |       | |  ****      |        |      ***************
   xxxCxxxxxxxCxCxxCxCxxxxxxxCxxxxxxxxCxxxxxxxCxCxCxxCxxxxxCxxxxxxxxxxx
                   | |                        | | |  |
                   | |                        | | +--+
                   +-|------------------------+ |
                     +--------------------------+

'C': conserved cysteine involved in a disulfide bond.
'*': position of the patterns.

We have developed two patterns for these hormones.  The  first one, located in
the N-terminal  section, is a region which has been said to be involved in the
association  between  the  two  chains  of  the hormones.  The  second pattern
consists of a cluster of five conserved cysteines in the C-terminal section.

-Consensus pattern: C-[STA]-G-[HYL]-C-x-[ST]
                    [The two C's are involved in disulfide bonds]
-Sequences known to belong to this class detected by the pattern: ALL,  except
 for rat beta-FSH which has Glu in position 2 of the pattern.
-Other sequence(s) detected in SWISS-PROT: NONE.

-Consensus pattern: [PA]-V-A-x(2)-C-x-C-x(2)-C-x(4)-[ST]-D-C-x(6)-[PST]-x(2)-C
                    [The five C's are involved in disulfide bonds]
-Sequences known to belong to this class detected by the pattern: ALL.
-Other sequence(s) detected in SWISS-PROT: NONE.

-Expert(s) to contact by email: Lapthorn A.
                                adrian@chem.gla.ac.uk

-Last update: March 1995 / Text revised.

[ 1] Pierce J.G., Parsons T.F.
     Annu. Rev. Biochem. 50:465-495(1981).
[ 2] Stockell Hartree A., Renwick A.G.C.
     Biochem. J. 287:665-679(1992).
[ 3] Lapthorn A.J., Harris D.C., Littlejohn A., Lustbader J.W., Canfield R.E.,
     Machin K.J., Morgan F.J., Isaacs N.W.
     Nature 369:455-461(1994).
{END}