extracellular domain (ECD) found in anti-Muellerian hormone type-2 receptor (AMHR2) and similar proteins; AMHR2 (EC 2.7.11.30, also called anti-Muellerian hormone type II receptor (MISRII), or AMH type II receptor, or MIS type II receptor, or MRII, on ligand binding) forms a receptor complex consisting of two type II and two type I transmembrane serine/threonine kinases. Type II receptors phosphorylate and activate type I receptors which autophosphorylate, then bind and activate SMAD transcriptional regulators. AMHR2 is the receptor for anti-Muellerian hormone. This model corresponds to the extracellular domain (ECD) of AMHR2, which belongs to Ly-6 antigen/uPA receptor-like (LU) superfamily and exhibits a snake toxin-like fold (also known as three-finger toxin/3FTx fold or three-fingered protein/TFP domain fold).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767973841  22 RTCVFFEAPGVRGSTKTLGelldtgTELPRAIRCLYSRCCFGIWNLTQDRAQVEMQGCRDSdEPGCESLHCDPSPRAHPS 101
Cdd:cd23616    1 RTCVFYVSPSNRGSLRAAG------NVSGSVQRCENTQCCVGIWNIINGQLQVDLLGCWVS-EASCPSATCKPSPRFNPN 73

                         90       100
                 ....*....|....*....|
gi 767973841 102 pgstLFTCSCGTDFCNANYS 121
Cdd:cd23616   74 ----YIKCVCNTDLCNGNIT 89

Protein Kinases, catalytic domain; The protein kinase superfamily is mainly composed of the catalytic domains of serine/threonine-specific and tyrosine-specific protein kinases. It also includes RIO kinases, which are atypical serine protein kinases, aminoglycoside phosphotransferases, and choline kinases. These proteins catalyze the transfer of the gamma-phosphoryl group from ATP to hydroxyl groups in specific substrates such as serine, threonine, or tyrosine residues of proteins.

                         10        20        30
                 ....*....|....*....|....*....|
gi 767973841 289 GLRELLEDCWDADPEARLTAECVQQRLAAL 318
Cdd:cd13998  260 SLAETIEECWDHDAEARLTAQCIEERLSEF 289

extracellular domain (ECD) found in anti-Muellerian hormone type-2 receptor (AMHR2) and similar proteins; AMHR2 (EC 2.7.11.30, also called anti-Muellerian hormone type II receptor (MISRII), or AMH type II receptor, or MIS type II receptor, or MRII, on ligand binding) forms a receptor complex consisting of two type II and two type I transmembrane serine/threonine kinases. Type II receptors phosphorylate and activate type I receptors which autophosphorylate, then bind and activate SMAD transcriptional regulators. AMHR2 is the receptor for anti-Muellerian hormone. This model corresponds to the extracellular domain (ECD) of AMHR2, which belongs to Ly-6 antigen/uPA receptor-like (LU) superfamily and exhibits a snake toxin-like fold (also known as three-finger toxin/3FTx fold or three-fingered protein/TFP domain fold).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767973841  22 RTCVFFEAPGVRGSTKTLGelldtgTELPRAIRCLYSRCCFGIWNLTQDRAQVEMQGCRDSdEPGCESLHCDPSPRAHPS 101
Cdd:cd23616    1 RTCVFYVSPSNRGSLRAAG------NVSGSVQRCENTQCCVGIWNIINGQLQVDLLGCWVS-EASCPSATCKPSPRFNPN 73

                         90       100
                 ....*....|....*....|
gi 767973841 102 pgstLFTCSCGTDFCNANYS 121
Cdd:cd23616   74 ----YIKCVCNTDLCNGNIT 89

Catalytic domain of Transforming Growth Factor beta Receptor-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of receptors for the TGFbeta family of secreted signaling molecules including TGFbeta, bone morphogenetic proteins (BMPs), activins, growth and differentiation factors (GDFs), and anti-Mullerian hormone, among others. These receptors contain an extracellular domain that binds ligands, a single transmembrane (TM) region, and a cytoplasmic catalytic kinase domain. There are two types of TGFbeta receptors included in this subfamily, I and II, that play different roles in signaling. For signaling to occur, the ligand first binds to the high-affinity type II receptor, which is followed by the recruitment of the low-affinity type I receptor to the complex and its activation through trans-phosphorylation by the type II receptor. The active type I receptor kinase starts intracellular signaling to the nucleus by phosphorylating SMAD proteins. Type I receptors contain an additional domain located between the TM and kinase domains called the the GS domain, which contains the activating phosphorylation site and confers preference for specific SMAD proteins. Different ligands interact with various combinations of types I and II receptors to elicit a specific signaling pathway. Activins primarily signal through combinations of ACVR1b/ALK7 and ACVR2a/b; myostatin and GDF11 through TGFbR1/ALK4 and ACVR2a/b; BMPs through ACVR1/ALK1 and BMPR2; and TGFbeta through TGFbR1 and TGFbR2. The TGFbR-like subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                         10        20        30
                 ....*....|....*....|....*....|
gi 767973841 289 GLRELLEDCWDADPEARLTAECVQQRLAAL 318
Cdd:cd13998  260 SLAETIEECWDHDAEARLTAQCIEERLSEF 289

extracellular domain (ECD) found in anti-Muellerian hormone type-2 receptor (AMHR2) and similar proteins; AMHR2 (EC 2.7.11.30, also called anti-Muellerian hormone type II receptor (MISRII), or AMH type II receptor, or MIS type II receptor, or MRII, on ligand binding) forms a receptor complex consisting of two type II and two type I transmembrane serine/threonine kinases. Type II receptors phosphorylate and activate type I receptors which autophosphorylate, then bind and activate SMAD transcriptional regulators. AMHR2 is the receptor for anti-Muellerian hormone. This model corresponds to the extracellular domain (ECD) of AMHR2, which belongs to Ly-6 antigen/uPA receptor-like (LU) superfamily and exhibits a snake toxin-like fold (also known as three-finger toxin/3FTx fold or three-fingered protein/TFP domain fold).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767973841  22 RTCVFFEAPGVRGSTKTLGelldtgTELPRAIRCLYSRCCFGIWNLTQDRAQVEMQGCRDSdEPGCESLHCDPSPRAHPS 101
Cdd:cd23616    1 RTCVFYVSPSNRGSLRAAG------NVSGSVQRCENTQCCVGIWNIINGQLQVDLLGCWVS-EASCPSATCKPSPRFNPN 73

                         90       100
                 ....*....|....*....|
gi 767973841 102 pgstLFTCSCGTDFCNANYS 121
Cdd:cd23616   74 ----YIKCVCNTDLCNGNIT 89

Catalytic domain of Transforming Growth Factor beta Receptor-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of receptors for the TGFbeta family of secreted signaling molecules including TGFbeta, bone morphogenetic proteins (BMPs), activins, growth and differentiation factors (GDFs), and anti-Mullerian hormone, among others. These receptors contain an extracellular domain that binds ligands, a single transmembrane (TM) region, and a cytoplasmic catalytic kinase domain. There are two types of TGFbeta receptors included in this subfamily, I and II, that play different roles in signaling. For signaling to occur, the ligand first binds to the high-affinity type II receptor, which is followed by the recruitment of the low-affinity type I receptor to the complex and its activation through trans-phosphorylation by the type II receptor. The active type I receptor kinase starts intracellular signaling to the nucleus by phosphorylating SMAD proteins. Type I receptors contain an additional domain located between the TM and kinase domains called the the GS domain, which contains the activating phosphorylation site and confers preference for specific SMAD proteins. Different ligands interact with various combinations of types I and II receptors to elicit a specific signaling pathway. Activins primarily signal through combinations of ACVR1b/ALK7 and ACVR2a/b; myostatin and GDF11 through TGFbR1/ALK4 and ACVR2a/b; BMPs through ACVR1/ALK1 and BMPR2; and TGFbeta through TGFbR1 and TGFbR2. The TGFbR-like subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767973841 208 QVIREGGHAVVWAGQLQGKLVAIKAFPPRSVAQFQAERALYELPGLQHDHIVRFITASRGGPGrLLSGPLLVLELHPKdp 287
Cdd:cd13998    1 EVIGKGRFGEVWKASLKNEPVAVKIFSSRDKQSWFREKEIYRTPMLKHENILQFIAADERDTA-LRTELWLVTAFHPN-- 77

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 767973841 288 DGLRELL-------EDCWD-ADPEARltaecvqqrlaALAHPQESHPfpeSCPRGCPPLCPEDCTS 345
Cdd:cd13998   78 GSL*DYLslhtidwVSLCRlALSVAR-----------GLAHLHSEIP---GCTQGKPAIAHRDLKS 129

Catalytic domain of the Serine/Threonine Kinase, Activin Type II Receptor; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. ACVR2 belongs to a group of receptors for the TGFbeta family of secreted signaling molecules that includes TGFbeta, bone morphogenetic proteins (BMPs), activins, growth and differentiation factors (GDFs), and anti-Mullerian hormone, among others. These receptors contain an extracellular domain that binds ligands, a single transmembrane region, and a cytoplasmic catalytic kinase domain. Type II receptors, such as ACVR2, are high-affinity receptors which bind ligands, autophosphorylate, as well as trans-phosphorylate and activate low-affinity type I receptors. ACVR2 acts primarily as the receptors for activins, nodal, myostatin, GDF11, and a subset of BMPs. ACVR2 signaling impacts many cellular and physiological processes including reproductive and gonadal functions, myogenesis, bone remodeling and tooth development, kidney organogenesis, apoptosis, fibrosis, inflammation, and neurogenesis. Vertebrates contain two ACVR2 proteins, ACVR2a (or ActRIIA) and ACVR2b (or ActRIIB). The ACVR2 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 767973841 218 VWAGQLQGKLVAIKAFPPRSVAQFQAERALYELPGLQHDHIVRFITASRGGPGrLLSGPLLVLELHPK 285
Cdd:cd14053   11 VWKAQYLNRLVAVKIFPLQEKQSWLTEREIYSLPGMKHENILQFIGAEKHGES-LEAEYWLITEFHER 77

Catalytic domain of Transforming Growth Factor beta Receptor-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of receptors for the TGFbeta family of secreted signaling molecules including TGFbeta, bone morphogenetic proteins (BMPs), activins, growth and differentiation factors (GDFs), and anti-Mullerian hormone, among others. These receptors contain an extracellular domain that binds ligands, a single transmembrane (TM) region, and a cytoplasmic catalytic kinase domain. There are two types of TGFbeta receptors included in this subfamily, I and II, that play different roles in signaling. For signaling to occur, the ligand first binds to the high-affinity type II receptor, which is followed by the recruitment of the low-affinity type I receptor to the complex and its activation through trans-phosphorylation by the type II receptor. The active type I receptor kinase starts intracellular signaling to the nucleus by phosphorylating SMAD proteins. Type I receptors contain an additional domain located between the TM and kinase domains called the the GS domain, which contains the activating phosphorylation site and confers preference for specific SMAD proteins. Different ligands interact with various combinations of types I and II receptors to elicit a specific signaling pathway. Activins primarily signal through combinations of ACVR1b/ALK7 and ACVR2a/b; myostatin and GDF11 through TGFbR1/ALK4 and ACVR2a/b; BMPs through ACVR1/ALK1 and BMPR2; and TGFbeta through TGFbR1 and TGFbR2. The TGFbR-like subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                         10        20        30
                 ....*....|....*....|....*....|
gi 767973841 289 GLRELLEDCWDADPEARLTAECVQQRLAAL 318
Cdd:cd13998  260 SLAETIEECWDHDAEARLTAQCIEERLSEF 289

Catalytic domain of the Serine/Threonine Kinase, Activin Type II Receptor; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. ACVR2 belongs to a group of receptors for the TGFbeta family of secreted signaling molecules that includes TGFbeta, bone morphogenetic proteins (BMPs), activins, growth and differentiation factors (GDFs), and anti-Mullerian hormone, among others. These receptors contain an extracellular domain that binds ligands, a single transmembrane region, and a cytoplasmic catalytic kinase domain. Type II receptors, such as ACVR2, are high-affinity receptors which bind ligands, autophosphorylate, as well as trans-phosphorylate and activate low-affinity type I receptors. ACVR2 acts primarily as the receptors for activins, nodal, myostatin, GDF11, and a subset of BMPs. ACVR2 signaling impacts many cellular and physiological processes including reproductive and gonadal functions, myogenesis, bone remodeling and tooth development, kidney organogenesis, apoptosis, fibrosis, inflammation, and neurogenesis. Vertebrates contain two ACVR2 proteins, ACVR2a (or ActRIIA) and ACVR2b (or ActRIIB). The ACVR2 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                         10        20        30
                 ....*....|....*....|....*....|.
gi 767973841 290 LRELLEDCWDADPEARLTAECVQQRLAALAH 320
Cdd:cd14053  259 LCETIEECWDHDAEARLSAGCVEERLSQLSR 289

Catalytic domain of the Serine/Threonine Kinase, Transforming Growth Factor beta Type II Receptor; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. TGFbR2 belongs to a group of receptors for the TGFbeta family of secreted signaling molecules that includes TGFbeta, bone morphogenetic proteins, activins, growth and differentiation factors, and anti-Mullerian hormone, among others. These receptors contain an extracellular domain that binds ligands, a single transmembrane region, and a cytoplasmic catalytic kinase domain. Type II receptors, such as TGFbR2, are high-affinity receptors which bind ligands, autophosphorylate, as well as trans-phosphorylate and activate low-affinity type I receptors. TGFbR2 acts as the receptor for TGFbeta, which is crucial in growth control and homeostasis in many different tissues. It plays roles in regulating apoptosis and in maintaining the balance between self renewal and cell loss. It also plays a key role in maintaining vascular integrity and in regulating responses to genotoxic stress. Mutations in TGFbR2 can cause aortic aneurysm disorders such as Loeys-Dietz and Marfan syndromes. The TGFbR2 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                         10        20        30
                 ....*....|....*....|....*....|
gi 767973841 290 LRELLEDCWDADPEARLTAECVQQRLAALA 319
Cdd:cd14055  266 LCDTITECWDHDPEARLTASCVAERFNELK 295

extracellular domain (ECD) found in bone morphogenetic protein receptor type-2 (BMPR-2) and similar proteins; BMPR2 (EC 2.7.11.30, also called BMP type-2 receptor, or bone morphogenetic protein receptor type II (BMPR-II), or BMP type II receptor) on ligand binding forms a receptor complex consisting of two type II and two type I transmembrane serine/threonine kinases. Type II receptors phosphorylate and activate type I receptors which autophosphorylate, then bind and activate SMAD transcriptional regulators. BMPR2 binds to BMP7, BMP2, and less efficiently, BMP4. The binding is weak, but enhanced by the presence of type I receptors for BMPs. It also mediates the induction of adipogenesis by GDF6. This model corresponds to the extracellular domain (ECD) of BMPR2, which belongs to Ly-6 antigen/uPA receptor-like (LU) superfamily and exhibits a snake toxin-like fold (also known as three-finger toxin/3FTx fold or three-fingered protein/TFP domain fold).

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 767973841  53 IRCLYSRCCFGIWNLTQD-RAQVEMQGC--RDSDEPGCESLHCDPSprAHPSP--GSTLFTCSCGTDFCNANYS 121
Cdd:cd23614   27 ILCVKGSQCYGLWEKTKEgEIRLVKQGCwsHIGDPQECHSEECVVT--TTPSSiqNGTYRFCCCSTDMCNVNFT 98

Catalytic domain of bacterial Serine/Threonine kinases, PknB and similar proteins; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily includes many bacterial eukaryotic-type STKs including Staphylococcus aureus PknB (also called PrkC or Stk1), Bacillus subtilis PrkC, and Mycobacterium tuberculosis Pkn proteins (PknB, PknD, PknE, PknF, PknL, and PknH), among others. S. aureus PknB is the only eukaryotic-type STK present in this species, although many microorganisms encode for several such proteins. It is important for the survival and pathogenesis of S. aureus as it is involved in the regulation of purine and pyrimidine biosynthesis, cell wall metabolism, autolysis, virulence, and antibiotic resistance. M. tuberculosis PknB is essential for growth and it acts on diverse substrates including proteins involved in peptidoglycan synthesis, cell division, transcription, stress responses, and metabolic regulation. B. subtilis PrkC is located at the inner membrane of endospores and functions to trigger spore germination. Bacterial STKs in this subfamily show varied domain architectures. The well-characterized members such as S. aureus and M. tuberculosis PknB, and B. subtilis PrkC, contain an N-terminal cytosolic kinase domain, a transmembrane (TM) segment, and mutliple C-terminal extracellular PASTA domains. The PknB subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767973841 207 QQVIREGGHAVVWAG--QLQGKLVAIKAFPP------RSVAQFQAE-RALYElpgLQHDHIVRFITAsrggpGRLLSGPL 277
Cdd:cd14014    5 VRLLGRGGMGEVYRArdTLLGRPVAIKVLRPelaedeEFRERFLREaRALAR---LSHPNIVRVYDV-----GEDDGRPY 76

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 767973841 278 LVLELHPKDPdgLRELLEDcwdadpEARLTAECV----QQRLAALAH 320
Cdd:cd14014   77 IVMEYVEGGS--LADLLRE------RGPLPPREAlrilAQIADALAA 115

Serine/threonine protein kinase [Signal transduction mechanisms];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767973841 208 QVIREGGHAVVWAG--QLQGKLVAIK------AFPPRSVAQFQAERALyeLPGLQHDHIVRFITASRGGPgrllsGPLLV 279
Cdd:COG0515   13 RLLGRGGMGVVYLArdLRLGRPVALKvlrpelAADPEARERFRREARA--LARLNHPNIVRVYDVGEEDG-----RPYLV 85

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|...
gi 767973841 280 LELHpkdpDG--LRELLEDCWDADPEARLtaECVQQRLAALAH 320
Cdd:COG0515   86 MEYV----EGesLADLLRRRGPLPPAEAL--RILAQLAEALAA 122

Catalytic domain of Mitogen-Activated Protein Kinase (MAPK) Kinase Kinase-like Serine/Threonine kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed mainly of MAP3Ks and similar proteins, including TGF-beta Activated Kinase-1 (TAK1, also called MAP3K7), MAP3K12, MAP3K13, Mixed lineage kinase (MLK), MLK-Like mitogen-activated protein Triple Kinase (MLTK), and Raf (Rapidly Accelerated Fibrosarcoma) kinases. MAP3Ks (MKKKs or MAPKKKs) phosphorylate and activate MAPK kinases (MAPKKs or MKKs or MAP2Ks), which in turn phosphorylate and activate MAPKs during signaling cascades that are important in mediating cellular responses to extracellular signals. Also included in this subfamily is the pseudokinase Kinase Suppressor of Ras (KSR), which is a scaffold protein that functions downstream of Ras and upstream of Raf in the Extracellular signal-Regulated Kinase (ERK) pathway.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767973841 210 IREGGHAVVWAGQLQGKLVAIKAFPPRS-----VAQFQAERALyeLPGLQHDHIVRFITASRGGPgrllsgPL-LVLELH 283
Cdd:cd13999    1 IGSGSFGEVYKGKWRGTDVAIKKLKVEDdndelLKEFRREVSI--LSKLRHPNIVQFIGACLSPP------PLcIVTEYM 72

                         90
                 ....*....|....
gi 767973841 284 PKdpdG-LRELLED 296
Cdd:cd13999   73 PG---GsLYDLLHK 83

Catalytic domain of the Serine/Threonine Kinase, Bone Morphogenetic Protein Type IA Receptor; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. BMPR1a, also called Activin receptor-Like Kinase 3 (ALK3), functions as a receptor for bone morphogenetic proteins (BMPs), which are involved in the regulation of cell proliferation, survival, differentiation, and apoptosis. BMPs are able to induce bone, cartilage, ligament, and tendon formation, and may play roles in bone diseases and tumors. Germline mutations in BMPR1a are associated with an increased risk to Juvenile Polyposis Syndrome, a hamartomatous disorder that may lead to gastrointestinal cancer. BMPR1a may also play an indirect role in the development of hematopoietic stem cells (HSCs) as osteoblasts are a major component of the HSC niche within the bone marrow. BMPR1a belongs to a group of receptors for the TGFbeta family of secreted signaling molecules that includes TGFbeta, BMPs, activins, growth and differentiation factors, and anti-Mullerian hormone, among others. These receptors contain an extracellular domain that binds ligands, a single transmembrane (TM) region, and a cytoplasmic catalytic kinase domain. Type I receptors, like BMPR1a, are low-affinity receptors that bind ligands only after they are recruited by the ligand/type II high-affinity receptor complex. Following activation, they start intracellular signaling to the nucleus by phosphorylating SMAD proteins. Type I receptors contain an additional domain located between the TM and kinase domains called the GS domain, which contains the activating phosphorylation site and confers preference for specific SMAD proteins. The BMPR1a subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 767973841 210 IREGGHAVVWAGQLQGKLVAIKAFPPRSVAQFQAERALYELPGLQHDHIVRFITASRGGPG 270
Cdd:cd14220    3 IGKGRYGEVWMGKWRGEKVAVKVFFTTEEASWFRETEIYQTVLMRHENILGFIAADIKGTG 63

Catalytic domain of the Serine/Threonine Kinase, Bone Morphogenetic Protein Type IB; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. BMPR1b, also called Activin receptor-Like Kinase 6 (ALK6), functions as a receptor for bone morphogenetic proteins (BMPs), which are involved in the regulation of cell proliferation, survival, differentiation, and apoptosis. BMPs are able to induce bone, cartilage, ligament, and tendon formation, and may play roles in bone diseases and tumors. Mutations in BMPR1b that led to inhibition of chondrogenesis can cause Brachydactyly (BD) type A2, a dominant hand malformation characterized by shortening and lateral deviation of the index fingers. A point mutation in the BMPR1b kinase domain is also associated with the Booroola phenotype, characterized by precocious differentiation of ovarian follicles. BMPR1b belongs to a group of receptors for the TGFbeta family of secreted signaling molecules that includes TGFbeta, BMPs, activins, growth and differentiation factors, and anti-Mullerian hormone, among others. These receptors contain an extracellular domain that binds ligands, a single transmembrane (TM) region, and a cytoplasmic catalytic kinase domain. Type I receptors, like BMPR1b, are low-affinity receptors that bind ligands only after they are recruited by the ligand/type II high-affinity receptor complex. Following activation, they start intracellular signaling to the nucleus by phosphorylating SMAD proteins. Type I receptors contain an additional domain located between the TM and kinase domains called the GS domain, which contains the activating phosphorylation site and confers preference for specific SMAD proteins. The BMPR1b subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 767973841 210 IREGGHAVVWAGQLQGKLVAIKAFPPRSVAQFQAERALYELPGLQHDHIVRFITASRGGPG 270
Cdd:cd14219   13 IGKGRYGEVWMGKWRGEKVAVKVFFTTEEASWFRETEIYQTVLMRHENILGFIAADIKGTG 73