SAM domain of Shank1,2,3 family proteins; SAM (sterile alpha motif) domain of Shank1,2,3 family proteins is a protein-protein interaction domain. Shank1,2,3 proteins are scaffold proteins that are known to interact with a variety of cytoplasmic and membrane proteins. SAM domains of the Shank1,2,3 family are prone to homooligomerization. They are highly enriched in the postsynaptic density, acting as scaffolds to organize assembly of postsynaptic proteins. SAM domains of Shank3 proteins can form large sheets of helical fibers. Shank genes show distinct patterns of expression, in rat Shank1 mRNA is found almost exclusively in brain, Shank2 in brain, kidney and liver, and Shank3 in heart, brain and spleen.

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gi 568947849 1243 PLGFWTKFDVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNIDRALKFFL 1308
Cdd:cd09506     1 PVHEWTVDDVGDWLESLNLGEHRERFMDNEIDGSHLPNLDKEDLTELGVTRVGHRMNIERALKKLL 66

SAM domain of Shank1,2,3 family proteins; SAM (sterile alpha motif) domain of Shank1,2,3 family proteins is a protein-protein interaction domain. Shank1,2,3 proteins are scaffold proteins that are known to interact with a variety of cytoplasmic and membrane proteins. SAM domains of the Shank1,2,3 family are prone to homooligomerization. They are highly enriched in the postsynaptic density, acting as scaffolds to organize assembly of postsynaptic proteins. SAM domains of Shank3 proteins can form large sheets of helical fibers. Shank genes show distinct patterns of expression, in rat Shank1 mRNA is found almost exclusively in brain, Shank2 in brain, kidney and liver, and Shank3 in heart, brain and spleen.

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gi 568947849 1243 PLGFWTKFDVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNIDRALKFFL 1308
Cdd:cd09506     1 PVHEWTVDDVGDWLESLNLGEHRERFMDNEIDGSHLPNLDKEDLTELGVTRVGHRMNIERALKKLL 66

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 568947849   1246 FWTKFDVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDY-VDLGVTRVGHRMNIDRALKFFLER 1310
Cdd:smart00454    3 QWSPESVADWLESIGLEQYADNFRKNGIDGALLLLLTSEEDlKELGITKLGHRKKILKAIQKLKEQ 68

SAM domain of Shank1,2,3 family proteins; SAM (sterile alpha motif) domain of Shank1,2,3 family proteins is a protein-protein interaction domain. Shank1,2,3 proteins are scaffold proteins that are known to interact with a variety of cytoplasmic and membrane proteins. SAM domains of the Shank1,2,3 family are prone to homooligomerization. They are highly enriched in the postsynaptic density, acting as scaffolds to organize assembly of postsynaptic proteins. SAM domains of Shank3 proteins can form large sheets of helical fibers. Shank genes show distinct patterns of expression, in rat Shank1 mRNA is found almost exclusively in brain, Shank2 in brain, kidney and liver, and Shank3 in heart, brain and spleen.

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gi 568947849 1243 PLGFWTKFDVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNIDRALKFFL 1308
Cdd:cd09506     1 PVHEWTVDDVGDWLESLNLGEHRERFMDNEIDGSHLPNLDKEDLTELGVTRVGHRMNIERALKKLL 66

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 568947849 1251 DVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNIDRALK 1305
Cdd:cd09487     1 DVAEWLESLGLEQYADLFRKNEIDGDALLLLTDEDLKELGITSPGHRKKILRAIQ 55

SAM domain of diacylglycerol kinase delta and eta subunits; SAM (sterile alpha motif) domain of DGK-eta-delta subfamily proteins is a protein-protein interaction domain. Proteins of this subfamily are multidomain diacylglycerol kinases with a SAM domain located at the C-terminus. DGK proteins participate in signal transduction. They regulate the level of second messengers such as diacylglycerol and phosphatidic acid. The SAM domain of DGK proteins can form high molecular weight homooligomers through head-to-tail interactions as well as heterooligomers between the SAM domains of DGK delta and eta proteins. The oligomerization plays a role in the regulation of DGK intracellular localization.

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gi 568947849 1243 PLGFWTKFDVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNIDRALK 1305
Cdd:cd09507     1 PVTNWTTEEVGAWLESLQLGEYRDIFARNDIRGSELLHLERRDLKDLGITKVGHVKRILQAIK 63

SAM domain (Sterile alpha motif);

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gi 568947849  1246 FWTKFDVADWLEWLGLSEHRAQFLDHEIDG-SHLPALTKEDYVDLGVTRVGHRMNIDRALK 1305
Cdd:pfam07647    3 SWSLESVADWLRSIGLEQYTDNFRDQGITGaELLLRLTLEDLKRLGITSVGHRRKILKKIQ 63

SAM domain of diacylglycerol kinase delta; SAM (sterile alpha motif) domain of DGK-delta subfamily proteins is a protein-protein interaction domain. Proteins of this subfamily are multidomain diacylglycerol kinases with a SAM domain located at the C-terminus. DGK-delta proteins participate in signal transduction. They regulate the level of second messengers such as diacylglycerol and phosphatidic acid. In particular DGK-delta is involved in the regulation of clathrin-dependent endocytosis. The SAM domain of DGK-delta proteins can form high molecular weight homooligomers through head-to-tail interactions as well as heterooligomers with the SAM domain of DGK-eta proteins. The oligomerization plays a role in the regulation of the DGK-delta intracellular localization: it inhibits the translocation of the protein to the plasma membrane from the cytoplasm. The SAM domain also can bind Zn at multiple (not conserved) sites driving the formation of highly ordered large sheets of polymers, thus suggesting that Zn may play important role in the function of DCK-delta.

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gi 568947849 1243 PLGFWTKFDVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNIDRALK 1305
Cdd:cd09575     1 PVHLWGTEEVAAWLEHLSLCEYKDIFTRHDVRGSELLHLERRDLKDLGVTKVGHMKRILCGIK 63

SAM domain of liprin-beta1,2 proteins repeat 2; SAM (sterile alpha motif) domain repeat 2 of liprin-beta1,2 proteins is a protein-protein interaction domain. Liprin-beta proteins contain three copies (repeats) of SAM domain. They may form heterodimers with liprin-alpha proteins through their SAM domains. It was suggested based on bioinformatic approaches that the second SAM domain of liprin-beta potentially is 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 568947849 1252 VADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNIDRALKF 1306
Cdd:cd09566     7 VLRWLDDIGLPQYKDAFSEAKVDGRMLHYLTVDDLLHLKVTSALHHASIRRGIQV 61

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 568947849 1247 WTKFDVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNIDRALK 1305
Cdd:cd09512     7 WSVQQVCQWLMGLGLEQYIPEFTANNIDGQQLLQLDSSKLKALGITSSSDRSLLKKKLK 65

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 568947849 1246 FWTKFDVADWLEWL-GLSEHRAQFLDHEIDGSHLPALTKEDYVDL 1289
Cdd:cd09509     3 KWSVDDVAQFIKSLdGCAEYAEVFREQEIDGQALLLLTEDDLLKG 47

SAM domain of MLTK subfamily; SAM (sterile alpha motif) domain of MLTK subfamily is a protein-protein interaction domain. Besides SAM domain, these proteins have N-terminal protein tyrosine kinase domain and leucine-zipper motif. Proteins of this group act as mitogen-activated protein triple kinase in a number of MAPK cascades. They can be activated by autophosphorylation in response to stress signals. MLTK-alpha is known to phosphorylate histone H3. In mammals, MLTKs participate in the activation of the JNK/SAPK, p38, ERK5 pathways, the transcriptional factor NF-kB, in the regulation of the cell cycle checkpoint, and in the induction of apoptosis in a hepatoma cell line. Some members of this subfamily are proto-oncogenes, thus MLTK-alpha is involved in neoplasmic cell transformation and/or skin cancer development in athymic nude mice. Based on in vivo coprecipitation experiments in mammalian cells, it has been demonstrated that MLTK proteins might form homodimers/oligomers via their SAM domains.

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gi 568947849 1247 WTKFDVADWLEWLG--------LSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNIDRAL 1304
Cdd:cd09529     2 WTEEDVHFWMQQLVrkgghpseLSQYADLFKENHITGKRLLLLTEEDLRDMGIGSKGHIIHLKSAI 67

SAM domain of BOI-like fungal subfamily; SAM (sterile alpha motif) domain of BOI-like fungal subfamily is a potential protein-protein interaction domain. Proteins of this subfamily are apparently scaffold proteins, since most contain SH3 and PH domains, which are also protein-protein interaction domains, in addition to SAM domain. BOI-like proteins participate in cell cycle regulation. In particular BOI1 and BOI2 proteins of budding yeast S.cerevisiae are involved in bud formation, and POB1 protein of fission yeast S.pombe plays a role in cell elongation and separation. Among binding partners of BOI-like fungal subfamily members are such proteins as Bem1 and Cdc42 (they are known to be involved in cell polarization and bud formation).

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gi 568947849 1247 WTKFDVADWLEWLGLSEHRAQ-FLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNI 1300
Cdd:cd09535     3 WSPEQVAEWLLSAGFDDSVCEkFRENEITGDILLELDLEDLKELDIGSFGKRFKL 57

SAM domain of Samd9/Samd9L subfamily; SAM (sterile alpha motif) domain of Samd9/Samd9L subfamily is a putative protein-protein interaction domain. SAM is a widespread domain in signaling proteins. Samd9 is a tumor suppressor gene. It is involved in death signaling of malignant glioblastoma. Samd9 suppression blocks cancer cell death induced by HVJ-E or IFN-beta treatment. Deleterious mutations in Samd9 lead to normophosphatemic familial tumoral calcinosis, a cutaneous disorder characterized by cutaneous calcification or ossification.

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gi 568947849 1247 WTKFDVADWLEWLGLSEHRAQFL-DHEIDGSHLPALTKEDYVDLGVTR 1293
Cdd:cd09528     3 WTKEHVKQWLIEDLIDKKYAEILyEEEVTGAVLKELTEEDLVDMGLPH 50

SAM domain of caskin protein repeat 2; SAM (sterile alpha motif) domain repeat 2 of caskin1,2 proteins is a protein-protein interaction domain. Caskin has two tandem SAM domains. Caskin protein is known to interact with membrane-associated guanylate kinase CASK, and may play a role in neural development, synaptic protein targeting, and regulation of gene expression.

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gi 568947849 1251 DVADWLEWLGLSEHRAQFLDHEIDG-SHLPALTKEDYVDLGVTRVGHRMNIDRALK 1305
Cdd:cd09498     9 DLLEWLSLLGLPQYHKVLVENGYDSiDFVTDLTWEDLQDIGITKLGHQKKLMLAIK 64

SAM domain of Scm-like-3MBT3,4 proteins of Polycomb group; SAM (sterile alpha motif) domain of Scm-like-3MBT3,4 (Sex comb on midleg, Malignant brain tumor) subfamily proteins (also known as L3mbtl3,4 proteins) is a putative protein-protein interaction domain. Proteins of this subfamily are predicted transcriptional regulators belonging to Polycomb group. The majority of them are multidomain proteins: in addition to the C-terminal SAM domain, they contain three MBT repeats and Zn finger domain. Murine L3mbtl3 protein of this subfamily is essential for maturation of myeloid progenitor cells during differentiation. Human L3mbtl4 is a potential tumor suppressor gene in breast cancer, while deregulation of L3MBTL3 is associated with neuroblastoma.

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gi 568947849 1247 WTKFDVADWLEWL-GLSEHRAQFLDHEIDGSHLPALTKEDYVDL 1289
Cdd:cd09582     4 WSVDEVAEFVQSLpGCEEHAKVFRDEQIDGEAFLLLTQSDLVKI 47

SAM domain ot SARM1-like proteins, repeat 1; SAM (sterile alpha motif) domain repeat 1 of SARM1-like adaptor proteins is a protein-protein interaction domain. SARM1-like proteins contain two tandem SAM domains. SARM1-like proteins are involved in TLR (Toll-like receptor) signaling. They are responsible for targeted localization of the whole protein to post-synaptic regions of axons. In humans SARM1 expression is detected in kidney and liver.

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gi 568947849 1247 WTKFDVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYV-DLGVT 1292
Cdd:cd09501     4 WSVADVQTWLKQIGFEDYAEKFSESQVDGDLLLQLTEDELKqDLGMS 50

SAM domain of Scm-like-4MBT proteins of Polycomb group; SAM (sterile alpha motif) domain of Scm-like-4MBT (Sex comb on midleg like, Malignant Brain Tumor) subfamily proteins of the polycomb group is a putative protein-protein interaction domain. Additionally to the SAM domain, most of the proteins of this subfamily have 4 MBT repeats. In Drosophila SAM-Scm-like-4MBT protein (known as dSfmbt) is a member of Pho repressive complex (PhoRC). Additionally to dSfmbt, the PhoRC complex includes Pho or Pho-like proteins. This complex is responsible for HOX (Homeobox) gene silencing: Pho or Pho-like proteins bind DNA and dSmbt binds methylated histones. dSmbt can interact with mono- and di-methylated histones H3 and H4 (however this activity has been shown for the MBT repeats, while exact function of the SAM domain is unclear). Besides interaction with histones, dSmbt can interact with Scm (a member of PRC complex), but this interaction also seems to be SAM domain independent.

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gi 568947849 1247 WTKFDVADWLEWLGLSEHRAQFLDHEIDGSHLPALTKEDYVDLGVTRVGHRMNI 1300
Cdd:cd09580     4 WGVKDVSQFLRENDCGAYCECFCRQNIDGKRLLSLTKEQIMTLTGMKVGPSLKI 57

SAM domain of AIDA1AB-like proteins, repeat 1; SAM (sterile alpha motif) domain repeat 1 of AIDA1AB-like proteins is a protein-protein interaction domain. AIDA1AB-like proteins have two tandem SAM domains. They may form an intramolecular head-to-tail homodimer. One of two basic motifs of the nuclear localization signal (NLS) is located within helix 5 of SAM2 (motif HKRK). This signal plays a role in decoupling of SAM2 from SAM1, thus facilitating translocation of this type proteins into the nucleus. SAM1 domain has a potential phosphorylation site for CMGC group of serine/threonine kinases. SAM domains of the AIDA1-like subfamily can directly bind ubiquitin and participate in regulating the degradation of ubiquitinated EphA receptors, particularly EPH-A8 receptor. Additionally AIDA1AB-like proteins may participate in the regulation of nucleoplasmic coilin protein interactions.

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gi 568947849 1252 VADWLEWLGLSEHRAQFLDHEID-----GSHLpaLTKEDYVDLGVTRVGHRMNIDRALK 1305
Cdd:cd09499     5 VGQWLESIGLPQYESKLLLNGFDdvdflGSGV--MEDQDLKEIGITDEQHRQIILQAAR 61

SAM domain of EPH-B3 subfamily of tyrosine kinase receptors; SAM (sterile alpha motif) domain of EPH-B3 subfamily of receptor tyrosine kinases is a C-terminal potential protein-protein interaction domain. This domain is located in the cytoplasmic region of EPH-B3 receptors and appears to mediate cell-cell initiated signal transduction. EPH-B3 receptor protein kinase performs kinase-dependent and kinase-independent functions. It is known to be involved in thymus morphogenesis, in regulation of cell adhesion and migration. Also EphB3 controls cell positioning and ordered migration in the intestinal epithelium and plays a role in the regulation of adult retinal ganglion cell axon plasticity after optic nerve injury. In some experimental models overexpression of EphB3 enhances cell/cell contacts and suppresses colon tumor growth.

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gi 568947849 1247 WTKF-DVADWLEWLGLSEHRAQFLDHEIDGSHLPA-LTKEDYVDLGVTRVGHRMNI 1300
Cdd:cd09553     3 YTTFtTVGDWLDAIKMGRYKENFVSAGFASFDLVAqMTAEDLLRIGVTLAGHQKKI 58