Sterile alpha motif; Widespread domain in signalling and nuclear proteins. In EPH-related tyrosine kinases, appears to mediate cell-cell initiated signal transduction via the binding of SH2-containing proteins to a conserved tyrosine that is phosphorylated. In many cases mediates homodimerisation.

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gi 1389712458   52 PWEWDVEDVVSWIINIGLPQYEKSFRKNFITGRRLIWIDSSSC-PKIGIQDFHDIQLITAAIRKI 115
Cdd:smart00454   1 VSQWSPESVADWLESIGLEQYADNFRKNGIDGALLLLLTSEEDlKELGITKLGHRKKILKAIQKL 65

SAM (Sterile alpha motif ); SAM (Sterile Alpha Motif) domain is a module consisting of approximately 70 amino acids. This domain is found in the Fungi/Metazoa group and in a restricted number of bacteria. Proteins with SAM domains are represented by a wide variety of domain architectures and have different intracellular localization, including nucleus, cytoplasm and membranes. SAM domains have diverse functions. They can interact with proteins, RNAs and membrane lipids, contain site of phosphorylation and/or kinase docking site, and play a role in protein homo and hetero dimerization/oligomerization in processes ranging from signal transduction to regulation of transcription. Mutations in SAM domains have been linked to several diseases.

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gi 1389712458  59 DVVSWIINIGLPQYEKSFRKNFITGRRLIWIDSSSCPKIGIQDFHDIQLITAAIRK 114
Cdd:cd09487     1 DVAEWLESLGLEQYADLFRKNEIDGDALLLLTDEDLKELGITSPGHRKKILRAIQR 56

SAM domain (Sterile alpha motif); It has been suggested that SAM is an evolutionarily conserved protein binding domain that is involved in the regulation of numerous developmental processes in diverse eukaryotes. The SAM domain can potentially function as a protein interaction module through its ability to homo- and heterooligomerise with other SAM domains.

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gi 1389712458  54 EWDVEDVVSWIINIGLPQYEKSFRKNFITGRRLIWIDSSSCPKIGIQDFHDIQLITAAIRKI 115
Cdd:pfam00536   2 GWSVEDVGEWLESIGLGQYIDSFRAGYIDGDALLQLTEDDLLKLGVTLLGHRKKILYAIQRL 63

SAM domain of Ste50_like (ubc2) subfamily; SAM (sterile alpha motif) domain of Ste50-like (or Ubc2 for Ustilago bypass of cyclase) subfamily is a putative protein-protein interaction domain. This group includes only fungal proteins. Basidiomycetes have an N-terminal SAM domain, central UBQ domain, and C-terminal SH3 domain, while Ascomycetes lack the SH3 domain. Ubc2 of Ustilago maydis is a major virulence and maize pathogenicity factor. It is required for filamentous growth (the budding haploid form of Ustilago maydis is a saprophyte, while filamentous dikaryotic form is a pathogen). Also the Ubc2 protein is involved in the pheromone-responsive morphogenesis via the MAP kinase cascade. The SAM domain is necessary for ubc2 function; deletion of SAM eliminates this function. A Lys-to-Glu mutation in the SAM domain of ubc2 gene induces temperature sensitivity.

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gi 1389712458  59 DVVSWIINIGLPQYEKSFRKNFITGRRLIWIDSSSCPKIGIQ 100
Cdd:cd09533     1 DVADWLSSLGLPQYEDQFIENGITGDVLVALDHEDLKEMGIT 42

SAM domain of SAM_Neurabin-like subfamily; SAM (sterile alpha motif) domain of Neurabin-like (Neural actin-binding) subfamily is a putative protein-protein interaction domain. This group currently includes the SAM domains of neurobin-I, SAMD14 and neurobin-I/SAMD14-like proteins. Most are multidomain proteins and in addition to SAM domain they contain other protein-binding domains such as PDZ and actin-binding domains. Members of this subfamily participate in signal transduction. Neurabin-I is involved in the regulation of Ca signaling intensity in alpha-adrenergic receptors; it forms a functional pair of opposing regulators with neurabin-II. Neurabins are expressed almost exclusively in neuronal cells. They are known to interact with protein phosphatase 1 and inhibit its activity; they also can bind actin filaments; however, the exact role of the SAM domain is unclear, since SAM doesn't participate in these interactions.

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gi 1389712458  53 WEWDVEDVVSWIINIGLPQYEKSFRKNFITGRRLIWIDSSSCPKIGIQDFHDIQLI 108
Cdd:cd09512     5 SEWSVQQVCQWLMGLGLEQYIPEFTANNIDGQQLLQLDSSKLKALGITSSSDRSLL 60

SAM domain of WDSUB1 proteins; SAM (sterile alpha motif) domain of WDSUB1 subfamily proteins is a putative protein-protein interaction domain. Proteins of this group contain multiple domains: SAM, one or more WD40 repeats and U-box (derived version of the RING-finger domain). Apparently the WDSUB1 subfamily proteins participate in protein degradation through ubiquitination, since U-box domain are known as a member of E3 ubiquitin ligase family, while SAM and WD40 domains most probably are responsible for an E2 ubiquitin-conjugating enzyme binding and a target protein binding.

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gi 1389712458  54 EWDVEDVVSWIINIGLPQYEKSFRKNFITGRRL 86
Cdd:cd09505     4 DWSEEDVCTWLRSIGLEQYVEVFRANNIDGKEL 36

SAM domain of STIM2 subfamily proteins; SAM (sterile alpha motif) domain of STIM2 (Stromal interaction molecule) subfamily proteins is a putative protein-protein interaction domain. STIM1 and STIM2 human proteins are type I transmembrane proteins. The N-terminal part of them includes "hidden" EF-hand and SAM domains. This region is responsible for sensing changes in store-operated and basal cytoplasmic Ca2+ levels and initiates oligomerization. "Hidden" EF hand and SAM domains have a stable intramolecular association, and the SAM domain is a component that regulates stability within STIM proteins. Destabilization of the EF-SAM association during Ca2+ depletion leads to partial unfolding and aggregation (homooligomerization), thus activating the store-operated Ca2+ entry. Immunoprecipitation analysis indicates that STIM1 and STIM2 can form co-precipitable oligomeric associations in vivo. It was suggested that STIM2 protein is an inhibitor of store operated channels in plasma membrane.

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gi 1389712458  55 WDVEDVVSWIIN-IGLPQYEKSFRKNFITGRRL 86
Cdd:cd09574     5 WTMEDTLQWLKEfVELPQYEKNFRDNNVKGTTL 37

SAM domain of STIM1 subfamily proteins; SAM (sterile alpha motif) domain of STIM1 (Stromal interaction molecule) subfamily proteins is a putative protein-protein interaction domain. STIM1 and STIM2 human proteins are type I transmembrane proteins. The N-terminal part of them includes "hidden" EF-hand and SAM domains. This region is responsible for sensing changes in store-operated and basal cytoplasmic Ca2+ levels and initiates oligomerization. "Hidden" EF hand and SAM domains have a stable intramolecular association, and the SAM domain is a component that regulates stability within STIM proteins. Destabilization of the EF-SAM association during Ca2+ depletion leads to partial unfolding and aggregation (homooligomerization), thus activating the store-operated Ca2+ entry. Immunoprecipitation analysis indicates that STIM1 and STIM2 can form co-precipitable oligomeric associations in vivo. It was suggested that STIM1 protein is an activator of store operated channels in plasma membrane.

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gi 1389712458  53 WEWDVEDVVSWIIN-IGLPQYEKSFRKNFITGRRL 86
Cdd:cd09573     3 YNWTVDEVVQWLITyVELPQYEETFRKLQLSGHAM 37

SAM domain of Polycomb group; SAM (sterile alpha motif) domain of Polycomb group is a protein-protein interaction domain. The Polycomb group includes transcriptional repressors which are involved in the regulation of some key regulatory genes during development in many organisms. They are best known for silencing Hox (Homeobox) genes. Polycomb proteins work together in large multimeric and chromatin-associated complexes. They organize chromatin of the target genes and maintain repressed states during many cell divisions. Polycomb proteins are classified based on their common function, but not on conserved domains and/or motifs; however many Polycomb proteins (members of PRC1 class complex) contain SAM domains which are more similar to each other inside of the Polycomb group than to SAM domains outside of it. Most information about structure and function of Polycomb SAM domains comes from studies of Ph (Polyhomeotic) and Scm (Sex comb on midleg) proteins. Polycomb SAM domains usually can be found at the C-terminus of the proteins. Some members of this group contain, in addition to the SAM domain, MTB repeats, Zn finger, and/or DUF3588 domains. Polycomb SAM domains can form homo- and/or heterooligomers through ML and EH surfaces. SAM/SAM oligomers apparently play a role in transcriptional repression through polymerization along the chromosome. Polycomb proteins are known to be highly expressed in some cells years before their cancer pathology; thus they are attractive markers for early cancer therapy.

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gi 1389712458  52 PWEWDVEDVVSWI-INIGLPQYEKSFRKNFITGRRL 86
Cdd:cd09509     1 PSKWSVDDVAQFIkSLDGCAEYAEVFREQEIDGQAL 36

SAM domain of liprin-beta1,2 proteins repeat 1; SAM (sterile alpha motif) domain repeat 1 of liprin-beta1,2 proteins is a protein-protein interaction domain. Liprin-beta protein contain three copies (repeats) of SAM domain. They may form heterodimers with liprins-alpha through their SAM domains. It was suggested based on bioinformatic approaches that the second SAM domain of liprin-beta is potentially able to form polymers. Liprins were originally identified as LAR (leukocyte common antigen-related) transmembrane protein-tyrosine phosphatase-interacting proteins. They participate in mammary gland development, in axon guidance, and in the maintenance of lymphatic vessel integrity.

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gi 1389712458  54 EWDVEDVVSWIINIGLPQYEKSFRKNFITGRRLI 87
Cdd:cd09563     3 EWSTEQVCDWLAELGLGQYVDECRRWVKSGQTLL 36

SAM domain of Atherin/Atherin-like subfamily; SAM (sterile alpha motif) domain of SAM_Atherin and Atherin-like subfamily proteins is a putative protein-protein and/or protein-lipid interaction domain. In addition to the C-terminal SAM domain, the majority of proteins belonging to this group also have PHD (or Zn finger) domain. As potential members of the polycomb group, these proteins may be involved in regulation of some key regulatory genes during development. Atherin can be recruited by Ruk/CIN85 kinase-binding proteins via its SH3 domains thus participating in the signal transferring kinase cascades. Also, atherin was found associated with low density lipids (LDL) in atherosclerotic lesions in human. It was suggested that atherin plays an essential role in atherogenesis via immobilization of LDL in the arterial wall. SAM domains of atherins are predicted to form polymers. Inhibition of polymer formation could be a potential antiatherosclerotic therapy.

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gi 1389712458  52 PWEWDVEDVVSWIINIGLPQYEKSFRKNFITGRRLI 87
Cdd:cd09583     1 PSNWSVEDVVQYFKTAGFPEEANAFKEQEIDGKSLL 36