SAM domain of Scm proteins of Polycomb group; SAM (sterile alpha motif) domain of Scm (Sex comb on midleg) subfamily of Polycomb group is a protein-protein interaction domain. Proteins of this subfamily are transcriptional repressors associated with PRC1 complex. This group includes invertebrate Scm protein and chordate Scm homolog 1 and Scm-like 1, 2, 3 proteins. Most have a SAM domain, two MBT repeats, and a DUF3588 domain, except Scm-like 4 proteins which do not have MBT repeats. Originally the Scm protein was described in Drosophila as a regulator required for proper spatial expression of homeotic genes. It plays a major role during early embryogenesis. SAM domains of Scm proteins can interact with each other, forming homooligomers, as well as with SAM domains of other proteins, in particular with SAM domains of Ph (polyhomeotic) proteins, forming heterooligomers. Homooligomers are similar to the ones formed by SAM Pointed domains of the TEL proteins. Such SAM/SAM oligomers apparently play a role in transcriptional repression through polymerization along the chromosome. Mammalian Scmh1 protein is known be indispensible member of PRC1 complex; it plays a regulatory role for the complex during meiotic prophase of male sperm cells, and is particularly involved in regulation of chromatin modification at the XY chromatin domain of the pachytene spermatocytes.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 21739503  63 SKDPSTWSVDEVIQFMKHTDPQISGPLADLFRQHEIDGKALFLLKSDVMMKYMGLKLGPALKLCYYIEKLKE 134
Cdd:cd09578   1 SKDPSTWSVEDVVQFIKEADPQALAPHVDLFRKHEIDGKALLLLNSDMMMKYMGLKLGPALKLCYHIDKLKQ 72

SAM domain of Scm proteins of Polycomb group; SAM (sterile alpha motif) domain of Scm (Sex comb on midleg) subfamily of Polycomb group is a protein-protein interaction domain. Proteins of this subfamily are transcriptional repressors associated with PRC1 complex. This group includes invertebrate Scm protein and chordate Scm homolog 1 and Scm-like 1, 2, 3 proteins. Most have a SAM domain, two MBT repeats, and a DUF3588 domain, except Scm-like 4 proteins which do not have MBT repeats. Originally the Scm protein was described in Drosophila as a regulator required for proper spatial expression of homeotic genes. It plays a major role during early embryogenesis. SAM domains of Scm proteins can interact with each other, forming homooligomers, as well as with SAM domains of other proteins, in particular with SAM domains of Ph (polyhomeotic) proteins, forming heterooligomers. Homooligomers are similar to the ones formed by SAM Pointed domains of the TEL proteins. Such SAM/SAM oligomers apparently play a role in transcriptional repression through polymerization along the chromosome. Mammalian Scmh1 protein is known be indispensible member of PRC1 complex; it plays a regulatory role for the complex during meiotic prophase of male sperm cells, and is particularly involved in regulation of chromatin modification at the XY chromatin domain of the pachytene spermatocytes.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 21739503  63 SKDPSTWSVDEVIQFMKHTDPQISGPLADLFRQHEIDGKALFLLKSDVMMKYMGLKLGPALKLCYYIEKLKE 134
Cdd:cd09578   1 SKDPSTWSVEDVVQFIKEADPQALAPHVDLFRKHEIDGKALLLLNSDMMMKYMGLKLGPALKLCYHIDKLKQ 72

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.

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 21739503     66 PSTWSVDEVIQFMKHTDPQisgPLADLFRQHEIDGKALFLLKSDVMMKYMG-LKLGPALKLCYYIEKLKE 134
Cdd:smart00454   1 VSQWSPESVADWLESIGLE---QYADNFRKNGIDGALLLLLTSEEDLKELGiTKLGHRKKILKAIQKLKE 67

SAM domain of Scm proteins of Polycomb group; SAM (sterile alpha motif) domain of Scm (Sex comb on midleg) subfamily of Polycomb group is a protein-protein interaction domain. Proteins of this subfamily are transcriptional repressors associated with PRC1 complex. This group includes invertebrate Scm protein and chordate Scm homolog 1 and Scm-like 1, 2, 3 proteins. Most have a SAM domain, two MBT repeats, and a DUF3588 domain, except Scm-like 4 proteins which do not have MBT repeats. Originally the Scm protein was described in Drosophila as a regulator required for proper spatial expression of homeotic genes. It plays a major role during early embryogenesis. SAM domains of Scm proteins can interact with each other, forming homooligomers, as well as with SAM domains of other proteins, in particular with SAM domains of Ph (polyhomeotic) proteins, forming heterooligomers. Homooligomers are similar to the ones formed by SAM Pointed domains of the TEL proteins. Such SAM/SAM oligomers apparently play a role in transcriptional repression through polymerization along the chromosome. Mammalian Scmh1 protein is known be indispensible member of PRC1 complex; it plays a regulatory role for the complex during meiotic prophase of male sperm cells, and is particularly involved in regulation of chromatin modification at the XY chromatin domain of the pachytene spermatocytes.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 21739503  63 SKDPSTWSVDEVIQFMKHTDPQISGPLADLFRQHEIDGKALFLLKSDVMMKYMGLKLGPALKLCYYIEKLKE 134
Cdd:cd09578   1 SKDPSTWSVEDVVQFIKEADPQALAPHVDLFRKHEIDGKALLLLNSDMMMKYMGLKLGPALKLCYHIDKLKQ 72

SAM domain of Ph (polyhomeotic) proteins of Polycomb group; SAM (sterile alpha motif) domain of Ph (polyhomeotic) proteins of Polycomb group is a protein-protein interaction domain. Ph1,2,3 proteins are members of PRC1 complex. This complex is involved in transcriptional repression of Hox (Homeobox) cluster genes. It is recruited through methylated H3Lys27 and supports the repression state by mediating monoubiquitination of histone H2A. Proteins of the Ph1,2,3 subfamily contribute to anterior-posterior neural tissue specification during embryogenesis. Additionally, the P2 protein of zebrafish is known to be involved in epiboly and tailbud formation. SAM domains of Ph proteins may interact with each other, forming homooligomers, as well as with SAM domains of other proteins, in particular with the SAM domain of Scm (sex comb on midleg) proteins, forming heterooligomers. Homooligomers are similar to the ones formed by SAM Pointed domains of the TEL proteins. Such SAM/SAM oligomers apparently play a role in transcriptional repression through polymerization along the chromosome.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 21739503  64 KDPSTWSVDEVIQFMKHTdPQISGpLADLFRQHEIDGKALFLLKSDVMMKYMGLKLGPALKLCYYIEKLKE 134
Cdd:cd09577   1 SNPSKWSVEDVYEFIRSL-PGCSD-YAEEFRAQEIDGQALLLLKEDHLMSAMNIKLGPALKICAKINSLKE 69

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 21739503  66 PSTWSVDEVIQFMKHTD-PQisgpLADLFRQHEIDGKALFLLK-SDVMMKyMGLKLGPALKLCYYIEKL 132
Cdd:cd09583   1 PSNWSVEDVVQYFKTAGfPE----EANAFKEQEIDGKSLLLLTrSDVLTG-LSLKLGPALKIYEHVVKL 64

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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 21739503    67 STWSVDEVIQFMKHTDPqisGPLADLFRQHEIDGKALFLLKSDVMMKYMGLKLGPALKLCYYIEKLK 133
Cdd:pfam00536   1 DGWSVEDVGEWLESIGL---GQYIDSFRAGYIDGDALLQLTEDDLLKLGVTLLGHRKKILYAIQRLK 64

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.

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 21739503     66 PSTWSVDEVIQFMKHTDPQisgPLADLFRQHEIDGKALFLLKSDVMMKYMG-LKLGPALKLCYYIEKLKE 134
Cdd:smart00454   1 VSQWSPESVADWLESIGLE---QYADNFRKNGIDGALLLLLTSEEDLKELGiTKLGHRKKILKAIQKLKE 67

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 21739503  66 PSTWSVDEVIQFMKHTDPQisgPLADLFRQHEIDGKALFLLKSDVMMKYMGLK-LGPALKLCYYIEKLKEGKYS 138
Cdd:cd09505   2 LQDWSEEDVCTWLRSIGLE---QYVEVFRANNIDGKELLNLTKESLSKDLKIEsLGHRNKILRKIEELKMKSDS 72

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 21739503  73 EVIQFMKHTDPqisGPLADLFRQHEIDGKALFLLkSDVMMKYMGLK-LGPALKLCYYIEK 131
Cdd:cd09487   1 DVAEWLESLGL---EQYADLFRKNEIDGDALLLL-TDEDLKELGITsPGHRKKILRAIQR 56

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 21739503  68 TWSVDEVIQFMKHTDPQISGP-----LADLFRQHEIDGKALFLLkSDVMMKYMGLK-LGPALKLCYYIEKLK 133
Cdd:cd09529   1 AWTEEDVHFWMQQLVRKGGHPselsqYADLFKENHITGKRLLLL-TEEDLRDMGIGsKGHIIHLKSAIEKLT 71

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 21739503  69 WSVDEVIQFMkhTDPQISGPLADLFRQHEIDGKALFLLKSDvMMKYMGLKLGPALKLCYYIEKLK 133
Cdd:cd09528   3 WTKEHVKQWL--IEDLIDKKYAEILYEEEVTGAVLKELTEE-DLVDMGLPHGPALLIIHSFNELN 64

SAM domain of DDHD2; SAM (sterile alpha motif) domain of DDHD2 group is a potential protein-protein interaction domain. DDHD2 proteins contain at least two domains:a SAM domain and a predicted metal-binding domain. Phospholipase A1 activity was demonstrated for the mammalian DDHD2 protein. Mutation of the putative catalytic serine resulted in elimination of activity. Unlike SEC23IP, DDHD2 proteins do not have an N-terminal proline-rich region and correspondingly they are not able to interact with Sec23p/Sec24p complex. Overexpression of DDHD2 is the cause of dispersion of ER/Golgi intermediate compartment and dispersion of tethering proteins located in the Golgi region, leading to aggregation in the endoplasmic reticulum.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21739503  91 DLFRQHEIDGKALFLLkSDVMMKYMGLKLGPALKLCYYIEKLKE 134
Cdd:cd09585  26 DVFEKEKIDLEALALC-QERDLKDLGIPLGPRKKILNYIRRRFL 68