{PDOC50105}
{PS50105; SAM_DOMAIN}
{BEGIN}
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* SAM domain profile *
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The sterile  alpha motif (SAM) domain is a putative protein interaction module
present in  a  wide  variety  of  proteins  [1]  involved  in  many biological
processes. The  SAM  domain  that  spreads over around 70 residues is found in
diverse eukaryotic  organisms  [2].  SAM  domains have been shown to homo- and
hetero-oligomerize [3],  nevertheless with a low-affinity constant [4], and to
mediate specific protein-protein interactions.

Structural analyses show that the SAM domain is arranged in a small five-helix
bundle with  two  large  interfaces  [3,4].   In the case of the SAM domain of
EphB2, each  of  these  interfaces is able to form dimers [4]. The presence of
these two  distinct  intermonomers binding surface suggest that SAM could form
extended polymeric structures [4].

Some of  the  proteins  in  which  such  a domain is known to exist are listed
below.

 - Vertebrate Eph receptor protein tyrosine kinases. Involved in developmental
   regulation.
 - Yeast  STE11,  serine/threonine protein kinase which participates in mating
   pheromone response pathways.
 - Mammalian  liprin  alpha. Interacts with LAR transmembrane protein tyrosine
   phosphatase.
 - Mammalian  Neurabin  actin  filament  binding  protein. Involved in neurite
   formation.
 - Mammalian inositol phosphatase protein Ship2.
 - Mammalian  SH2  domain-containing  leukocyte  Protein  of  76kDa  (SLP-76).
   Hematopoietic cell specific molecule, critical for T cell development.
 - Mammalian ETS translocation variant (ETV) or TEL. Translocations which fuse
   the SAM  domain  from  ETV to Abl, PDGFB, JAK2 or AML1 have been associated
   with many human leukemias.
 - Drosophila  polyhomeotic  (ph)  and Sex comb on midleg (Scm), member of the
   Polycomb group genes, implied in the transcriptional repression of homeotic
   genes.
 - Mammalian   Polycomb  group  proteins  Rae-28/MPH1 and SCML1. Homologues of
   drosophila ph and Scm proteins.

We developed a profile that spans the whole domain.

-Sequences known to belong to this class detected by the profile: ALL.
-Other sequence(s) detected in Swiss-Prot: 1.
-Last update: December 2001 / First entry.

[ 1] Schultz J., Ponting C.P., Hofmann K., Bork P.
     "SAM as a protein interaction domain involved in developmental
     regulation."
     Protein Sci. 6:249-253(1997).
     PubMed=9007998
[ 2] Stapleton D., Balan I., Pawson T., Sicheri F.
     "The crystal structure of an Eph receptor SAM domain reveals a
     mechanism for modular dimerization."
     Nat. Struct. Biol. 6:44-49(1999).
     PubMed=9886291; DOI=10.1038/4917
[ 3] Peterson A.J., Kyba M., Bornemann D., Morgan K., Brock H.W., Simon J.
     "A domain shared by the Polycomb group proteins Scm and ph mediates
     heterotypic and homotypic interactions."
     Mol. Cell. Biol. 17:6683-6692(1997).
     PubMed=9343432
[ 4] Thanos C.D., Goodwill K.E., Bowie J.U.
     "Oligomeric structure of the human EphB2 receptor SAM domain."
     Science 283:833-836(1999).
     PubMed=9933164
{END}