******************************
* LIF / OSM family signature *
******************************

On the  basis  of  functional and structural similarities, the following small
cytokines can be classified into a single family [1,2]:

 - Leukemia inhibitory factor (LIF) (also known as differentiation-stimulating
   factor). LIF is a mammalian growth factor that controls the differentiation
   and proliferation of   hematopoietic  cells  as  well  as those of  several
   other cellular lineages.
 - Oncostatin (OSM),  a growth  regulator  produced  by a  number of mammalian
   cells lines.  OSM  is capable of inhibiting  the replication of a number of
   tumor cells.   It  may  play  a  role  in  the  regulation  and  growth  of
   hematopoietic cells.

As a signature pattern for these cytokines, we selected a  conserved region in
their C-terminal section.  This  region  is  centered on a  conserved cysteine
which  has  been  shown [3],  in  OSM, to be involved in a disulfide bond. The
C-terminal part  of  this  region  is  very  hydrophobic  and  is  known to be
essential to the biological activity of OSM.

-Consensus pattern: G-x(13)-[DE]-x-F-Q-[KR]-K-x(2)-G-C-x(2)-L-x(2)-Y-x(3)-
                    [LIVM]-x(2)-[LIVM]-x(3)-F
                    [C is involved in a disulfide bond]
-Sequences known to belong to this class detected by the pattern: ALL.
-Other sequence(s) detected in SWISS-PROT: NONE.

-Note: it has been said [2]  that  LIF and OSM can  be  included  in  the IL-6
 family of cytokines (see the relevant entry), but  while  all these cytokines
 seem to be structurally related,  the sequence similarity  is not high enough
 to allow the use of a single consensus pattern.

-Last update: June 1992 / Text revised.

[ 1] Hilton D.J.
     Trends Biochem. Sci. 17:72-76(1992).
[ 2] Rose T.M., Bruce A.G.
     Proc. Natl. Acad. Sci. U.S.A. 88:8641-8645(1991).
[ 3] Kallestad J.C., Shoyab M., Linsley P.S.
     J. Biol. Chem. 266:8940-8945(1991).