TI  - The three human  syntrophin  genes are expressed in diverse tissues, have
      distinct chromosomal locations, and each bind to  <prot>dystrophin</prot>  and its
      relatives.
PG  - 2724-30
AB  - The  syntrophins  are a biochemically heterogeneous group of 58-kDa
      intracellular membrane-associated  <prot>dystrophin</prot> -binding proteins. We have
      cloned and characterized human <prot>acidic (alpha 1-) syntrophin</prot> and a second
      isoform of human <prot>basic (beta 2-) syntrophin</prot>. Comparison of the deduced
      amino acid structure of the three human isoforms of syntrophin (together
      with the previously reported human <prot>beta 1-syntrophin</prot>) demonstrates their
      overall similarity. The deduced amino acid sequences of human alpha 1- and
      <prot>beta 2-syntrophin</prot> are nearly identical to their homologues in mouse,
      suggesting a strong functional conservation among the individual isoforms,
      Much like <prot>beta 1-syntrophin</prot>, human <prot>beta 2-syntrophin</prot> has multiple
      transcript classes and is expressed widely, although in a distinct pattern
      of relative abundance. In contrast, human <prot>alpha 1-syntrophin</prot> is most
      abundant in heart and skeletal muscle, and less so in other tissues.
      Somatic cell hybrids and fluorescent in situ hybridization were both used
      to determine their chromosomal locations: <prot>beta 2-syntrophin</prot> to chromosome
      16q22-23 and <prot>alpha 1-syntrophin</prot> to chromosome 20q11.2. Finally, we used in
      vitro translated proteins in an immunoprecipitation assay to show that,
      like  <prot>beta 1-syntrophin</prot> , both beta 2-  and  <prot>alpha 1-syntrophin</prot>  interact with
      peptides encoding the syntrophin-binding region of    <prot>dystrophin</prot>  ,
      <prot>utrophin</prot>/<prot><prot>dystrophin</prot> related protein</prot>, and the <prot>Torpedo 87K protein</prot>.
AD  - Program in Neuroscience, Harvard Medical School, Boston, Massachusetts
