{PDOC00239}
{PS00266; SOMATOTROPIN_1}
{PS00338; SOMATOTROPIN_2}
{BEGIN}
***********************************************************
* Somatotropin, prolactin and related hormones signatures *
***********************************************************

The hormone somatotropin (growth hormone, GH)  which  plays  an important role
in growth control, choriomammotropin (lactogen), a placental analog of GH; and
prolactin which acts primarily  on  the  mammary gland by promoting lactation,
have been shown [1]  to be homologous.  This family  of proteins also includes
other hormones  listed  below    (references  are  only  provided for recently
determined sequences).

 - Rodents placental lactogens I and II.
 - Bovine and sheep lactogen.
 - Mouse proliferin I, II, III and proliferin related protein [2].
 - Bovine placental prolactin-related proteins I, II, and III [3].
 - Rat placental prolactin-like proteins A and B.
 - Human growth hormone variants 1 (GH-V1) and 2 (GH-V2).
 - Somatolactin (SL) from various fish [4].

The schematic representation  of  the  structure of proteins belonging to this
family is shown below.

        <----------------180-to-210-residues------------->
                     ***                          *****
        xxxxxxxxxxxxxCxxxxxxxxxxxxxxxxxxxxxxxxxxxxCxxxCxxC
                     |                            |   |  |
                     +----------------------------+   +--+

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

We developed two signature patterns for this family of proteins, both patterns
include cysteines involved in conserved disulfide bonds.

-Consensus pattern: C-x-[STN]-x(2)-[LIVMFYS]-x-[LIVMSTA]-P-x(5)-[TALIV]-x(7)-
                    [LIVMFY]-x(6)-[LIVMFY]-x(2)-[STACV]-W
                    [The C is involved in disulfide bonds]
-Sequences known to belong to this class detected by the pattern: ALL,  except
 for 8 sequences.
-Other sequence(s) detected in Swiss-Prot: 4.

-Consensus pattern: C-[LIVMFY]-{PT}-x-D-[LIVMFYSTA]-x-{S}-{RK}-{A}-x-[LIVMFY]-
                    x(2)-[LIVMFYT]-x(2)-C
                    [The 2 C's are involved in disulfide bonds]
-Sequences known to belong to this class detected by the pattern: ALL,  except
 for 7 sequences.
-Other sequence(s) detected in Swiss-Prot: 16.

-Last update: April 2006 / Pattern revised.

[ 1] Wallis M.
     "Episodic evolution of protein hormones in mammals."
     J. Mol. Evol. 53:10-18(2001).
     PubMed=11683318
[ 2] Connor A.M., Waterhouse P., Khokha R., Denhardt D.T.
     "Characterization of a mouse mitogen-regulated protein/proliferin gene
     and its promoter: a member of the growth hormone/prolactin gene
     superfamily."
     Biochim. Biophys. Acta 1009:75-82(1989).
     PubMed=2790033
[ 3] Kessler M.A., Milosavljevic M., Zieler C.G., Schuler L.A.
     "A subfamily of bovine prolactin-related transcripts distinct from
     placental lactogen in the fetal placenta."
     Biochemistry 28:5154-5161(1989).
     PubMed=2765528
[ 4] Rand-Weaver M., Noso T., Muramoto K., Kawauchi H.
     Biochemistry 30:1509-1515(1991).
{END}