*********************************
* Uteroglobin family signatures *
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Uteroglobin [1] is a protein that seems specific to lagomorphes (rabbit, hare,
and pica) and which binds progesterone specifically and with high affinity. It
may regulate  progesterone concentrations reaching the blastocyst. Uteroglobin
is also  a  potent  inhibitor of phospholipase A2. It is a protein of 70 amino
acids that    form  antiparallel  disulfide-linked  dimers.  The progesterone-
binding site is formed by a cavity between the monomeric subunits. A schematic
representation of the location of the two disulfide  bonds in the antiparallel
dimer is shown below:

 NH2-xxCxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxCx-COOH
       |                                                              |
 COOH-xCxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxCxx-NH2

Two proteins are known to be structurally related to uteroglobin:

 - Clara  cell  10  Kd  secretory  protein  (CC10)  [2,3].  CC10  is a protein
   expressed by non-ciliated cells of pulmonary airway surface epithelium. Its
   exact function  is  not  known.  CC10, like uteroglobin, is an inhibitor of
   phospholipase A2.  It  binds  to  polychlorinated biphenyls (PCB). Rat CC10
   binds strongly to progesterone while human CC10 binds only weakly.
 - Domestic cat major allergen I chain 1 (fel DI) [4].

We derived  two  signature  patterns  specific to proteins that belong to this
family. These  are  centered  around  the  two  cysteine  residues involved in
interchain disulfide bonds.

-Consensus pattern: [GA]-x(3)-I-C-P-x-[LIVMF]-x(3)-[LIVM]-[DE]-x-[LIVMF](2)
                    [C is involved in an interchain disulfide bond]
-Sequences known to belong to this class detected by the pattern: ALL.
-Other sequence(s) detected in SWISS-PROT: NONE.

-Consensus pattern: [DE]-K-I-x(2)-S-x-L-C
                    [C is involved in an interchain disulfide bond]
-Sequences known to belong to this class detected by the pattern: ALL.
-Other sequence(s) detected in SWISS-PROT: NONE.

-Last update: October 1993 / Patterns and text revised.

[ 1] Bally R., Delettre J.
     J. Mol. Biol. 206:153-170(1989).
[ 2] Singh G., Katyal S.L., Brown W.E., Kennedy A.L., Singh U.,
     Wong-Chong M.-L.
     Biochim. Biophys. Acta 1039:348-355(1990).
[ 3] Nordlund-Moller L., Andersson O., Ahlgren R., Schilling J., Gillner M.,
     Gustafsson J.-A., Lund J.
     J. Biol. Chem. 265:12690-12693(1990).
[ 4] Morgenstern J.P., Griffith I.J., Brauer A.W., Rogers B.L., Bond J.F.,
     Chapman M.D., Kuo M.-C.
     Proc. Natl. Acad. Sci. U.S.A. 88:9690-9694(1991).