calponin homology (CH) domain superfamily; CH domains are actin filament (F-actin) binding motifs, which may be present as a single copy or in tandem repeats (which increase binding affinity). They either function as autonomous actin binding motifs or serve a regulatory function. CH domains are found in cytoskeletal and signal transduction proteins, including actin-binding proteins like spectrin, alpha-actinin, dystrophin, utrophin, and fimbrin, as well as proteins essential for regulation of cell shape (cortexillins), and signaling proteins (Vav).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  327 KAFAKVGFIPTYRQSFIENYDYQAKGFS-DFSDGLILAKLLEtvgeMPHGQ--ILLKLRDPAGDRIRKIGNVKIVLQEMS 403
Cdd:cd21223    3 RHLGYLGYVLSHVQTPLDEFDFAVTNLAvDLRDGVRLCRLVE----LLTGDwsLLSKLRVPAISRLQKLHNVEVALKALK 78

                         90       100       110
                 ....*....|....*....|....*....|....*
gi 17506033  404 SLGVPTD----NVNAESIVGGKKDEILSILWAIIG 434
Cdd:cd21223   79 EAGVLRGgdggGITAKDIVDGHREKTLALLWRIIF 113

first calponin homology (CH) domain found in abnormal spindle-like microcephaly-associated protein (ASPM) and similar proteins; ASPM, also called abnormal spindle protein homolog, or Asp homolog, is involved in mitotic spindle regulation and coordination of mitotic processes. It may also have a preferential role in regulating neurogenesis. Members of this family contain two copies of the CH domain in the middle region. This model corresponds to the first CH domain. CH domains are actin filament (F-actin) binding motifs.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  327 KAFAKVGFIPTYRQSFIENYDYQAKGFS-DFSDGLILAKLLEtvgeMPHGQ--ILLKLRDPAGDRIRKIGNVKIVLQEMS 403
Cdd:cd21223    3 RHLGYLGYVLSHVQTPLDEFDFAVTNLAvDLRDGVRLCRLVE----LLTGDwsLLSKLRVPAISRLQKLHNVEVALKALK 78

                         90       100       110
                 ....*....|....*....|....*....|....*
gi 17506033  404 SLGVPTD----NVNAESIVGGKKDEILSILWAIIG 434
Cdd:cd21223   79 EAGVLRGgdggGITAKDIVDGHREKTLALLWRIIF 113

Calponin homology (CH) domain; The CH domain is found in both cytoskeletal proteins and signal transduction proteins. The CH domain is involved in actin binding in some members of the family. However in calponins there is evidence that the CH domain is not involved in its actin binding activity. Most member proteins have from two to four copies of the CH domain, however some proteins such as calponin have only a single copy.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033    353 FSDFSDGLILAKLLETVgeMPHgqiLLKLRDPAGDRIRKIGNVKIVLQE-MSSLGVPTDNVNAESIVGGKKDEILSILWA 431
Cdd:pfam00307   28 TTDLRDGLALCALLNKL--APG---LVDKKKLNKSEFDKLENINLALDVaEKKLGVPKVLIEPEDLVEGDNKSVLTYLAS 102

                   ..
gi 17506033    432 II 433
Cdd:pfam00307  103 LF 104

IQ calmodulin-binding motif; Calmodulin-binding motif.

                           10        20
                   ....*....|....*....|.
gi 17506033    960 KKAAVVIQKMIRGFIARRKFQ 980
Cdd:pfam00612    1 RKAAIKIQAAWRGYLARKRYK 21

first calponin homology (CH) domain found in abnormal spindle-like microcephaly-associated protein (ASPM) and similar proteins; ASPM, also called abnormal spindle protein homolog, or Asp homolog, is involved in mitotic spindle regulation and coordination of mitotic processes. It may also have a preferential role in regulating neurogenesis. Members of this family contain two copies of the CH domain in the middle region. This model corresponds to the first CH domain. CH domains are actin filament (F-actin) binding motifs.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  327 KAFAKVGFIPTYRQSFIENYDYQAKGFS-DFSDGLILAKLLEtvgeMPHGQ--ILLKLRDPAGDRIRKIGNVKIVLQEMS 403
Cdd:cd21223    3 RHLGYLGYVLSHVQTPLDEFDFAVTNLAvDLRDGVRLCRLVE----LLTGDwsLLSKLRVPAISRLQKLHNVEVALKALK 78

                         90       100       110
                 ....*....|....*....|....*....|....*
gi 17506033  404 SLGVPTD----NVNAESIVGGKKDEILSILWAIIG 434
Cdd:cd21223   79 EAGVLRGgdggGITAKDIVDGHREKTLALLWRIIF 113

Calponin homology domain; Actin binding domains present in duplicate at the N-termini of spectrin-like proteins (including dystrophin, alpha-actinin). These domains cross-link actin filaments into bundles and networks. A calponin homology domain is predicted in yeasst Cdc24p.

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033     353 FSDFSDGLILAKLLETVgeMPhGQILLKLRDPAGDRIRKIGNVKIVLQEMSSLGVPTDNVNAESIVGGKKDeILSILWAI 432
Cdd:smart00033   23 SSDLKDGVALCALLNSL--SP-GLVDKKKVAASLSRFKKIENINLALSFAEKLGGKVVLFEPEDLVEGPKL-ILGVIWTL 98

                    .
gi 17506033     433 I 433
Cdd:smart00033   99 I 99

first calponin homology (CH) domain found in the plastin/fimbrin family; This family includes plastin and fimbrin. Plastin has three isoforms, plastin-1, -2, and -3, which are all actin-bundling proteins. Plastin-1, also called intestine-specific plastin, or I-plastin, is an actin-bundling protein in the absence of calcium. Plastin-2, also called L-plastin, LC64P, or lymphocyte cytosolic protein 1 (LCP-1), plays a role in the activation of T-cells in response to costimulation through TCR/CD3 and CD2 or CD28. It modulates the cell surface expression of IL2RA/CD25 and CD69. Plastin-3, also called T-plastin, is found in intestinal microvilli, hair cell stereocilia, and fibroblast filopodia. It may play a role in the regulation of bone development. Fimbrin has been found in plants and fungi. Arabidopsis thaliana fimbrin (AtFIM) includes fimbrin-1, -2, -3, -4, and -5; they cross-link actin filaments (F-actin) in a calcium independent manner. They stabilize and prevent F-actin depolymerization mediated by profilin. They act as key regulators of actin cytoarchitecture, probably involved in cell cycle, cell division, cell elongation and cytoplasmic tractus. AtFIM5 is an actin bundling factor that is required for pollen germination and pollen tube growth. Fungal fimbrin binds to actin, and functionally associates with actin structures involved in the development and maintenance of cell polarity. Members of this family contain four copies of the CH domain. This model corresponds to the first CH domain. CH domains are actin filament (F-actin) binding motifs.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  353 FSDFSDGLILAKLLETVgeMPHGQILLKL-RDPAGDRIRKIGNVKIVLQEMSSLGVPTDNVNAESIVGGKKDEILSILWA 431
Cdd:cd21217   34 FEALRDGVLLCKLINKI--VPGTIDERKLnKKKPKNIFEATENLNLALNAAKKIGCKVVNIGPQDILDGNPHLVLGLLWQ 111

                 ..
gi 17506033  432 II 433
Cdd:cd21217  112 II 113

first calponin homology (CH) domain found in the beta spectrin family; The beta spectrin family includes beta-I, -II, -III, -IV and -V spectrins. Spectrin is an actin crosslinking and molecular scaffold protein that links the plasma membrane to the actin cytoskeleton, and functions in the determination of cell shape, arrangement of transmembrane proteins, and organization of organelles. It is composed of two antiparallel dimers of alpha- and beta- subunits. Beta-I spectrin, also called spectrin beta chain, erythrocytic (SPTB), may be involved in anaemia pathogenesis. Beta-II spectrin, also called spectrin beta chain, non-erythrocytic 1 (SPTBN1), or fodrin beta chain, is a component of fodrin, which is the general spectrin-like protein that seems to be involved in secretion. Fodrin interacts with calmodulin in a calcium-dependent manner and is thus a candidate for the calcium-dependent movement of the cytoskeleton at the membrane. Beta-IV spectrin is also called spectrin, non-erythroid beta chain 3 (SPTBN3) or spectrin beta chain, non-erythrocytic 4 (SPTBN4). Its mutation associates with congenital myopathy, neuropathy, and central deafness. Beta-III spectrin is also called spectrin beta chain, non-erythrocytic 2 (SPTBN2), or spinocerebellar ataxia 5 protein (SCA5). Beta-V spectrin, also called spectrin beta chain, non-erythrocytic 5 (SPTBN5), is a mammalian ortholog of Drosophila beta H spectrin. Beta-III and Beta-V spectrins may play crucial roles as longer actin-membrane cross-linkers or fulfill the need for greater extensible flexibility than can be provided by the other smaller conventional spectrins. Members of this family contain two copies of the CH domain. This model corresponds to the first CH domain. CH domains are actin filament (F-actin) binding motifs.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  353 FSDFSDGLILAKLLETV-GEmphgqillKLRDPAGDRIR--KIGNVKIVLQEMSSlGVPTDNVNAESIVGGKKDEILSIL 429
Cdd:cd21193   40 FTDLSDGKLLLKLLEIIsGE--------KLGKPNRGRLRvqKIENVNKALAFLKT-KVRLENIGAEDIVDGNPRLILGLI 110

                 ....
gi 17506033  430 WAII 433
Cdd:cd21193  111 WTII 114

calponin homology (CH) domain found in neuron navigator (NAV) 2, NAV3, and similar proteins; This family includes neuron navigator 2 (NAV2) and NAV3, both of which contain a single copy of the CH domain at the N-terminus. CH domains are actin filament (F-actin) binding motifs. NAV2, also called helicase APC down-regulated 1 (HELAD1), pore membrane and/or filament-interacting-like protein 2 (POMFIL2), retinoic acid inducible in neuroblastoma 1 (RAINB1), Steerin-2 (STEERIN2), or Unc-53 homolog 2 (unc53H2), possesses 3' to 5' helicase activity and exonuclease activity. It is involved in neuronal development, specifically in the development of different sensory organs. NAV3, also called pore membrane and/or filament-interacting-like protein 1 (POMFIL1), Steerin-3 (STEERIN3), or Unc-53 homolog 3 (unc53H3), may regulate IL2 production by T-cells. It may be involved in neuron regeneration.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  354 SDFSDGLILAKLLETV-GEMPHGqillKLRDPAgDRIRKIGNVKIVLQEMSSLGVPTDNVNAESIVGGKKDEILSILWAI 432
Cdd:cd21212   27 KDLGDGLTLVNLIEAVaGEKVPG----IHSRPK-TRAQKLENIQACLQFLAALGVDVQGITAEDIVDGNLKAILGLFFSL 101

calponin homology (CH) domain superfamily; CH domains are actin filament (F-actin) binding motifs, which may be present as a single copy or in tandem repeats (which increase binding affinity). They either function as autonomous actin binding motifs or serve a regulatory function. CH domains are found in cytoskeletal and signal transduction proteins, including actin-binding proteins like spectrin, alpha-actinin, dystrophin, utrophin, and fimbrin, as well as proteins essential for regulation of cell shape (cortexillins), and signaling proteins (Vav).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  353 FSDFSDGLILAKLLETVgempHGQILLKLRDPAGDRIRKIGNVKIVLQEMSSLGVP-TDNVNAESIVGGKKDE-ILSILW 430
Cdd:cd00014   24 FESLRDGVLLCKLINKL----SPGSIPKINKKPKSPFKKRENINLFLNACKKLGLPeLDLFEPEDLYEKGNLKkVLGTLW 99

                 ...
gi 17506033  431 AII 433
Cdd:cd00014  100 ALA 102

IQ calmodulin-binding motif; Calmodulin-binding motif.

                           10        20
                   ....*....|....*....|.
gi 17506033    960 KKAAVVIQKMIRGFIARRKFQ 980
Cdd:pfam00612    1 RKAAIKIQAAWRGYLARKRYK 21

first calponin homology (CH) domain found in spectrin beta chain, non-erythrocytic 4 (SPTBN4) and similar proteins; Spectrin is an actin crosslinking and molecular scaffold protein that links the plasma membrane to the actin cytoskeleton, and functions in the determination of cell shape, arrangement of transmembrane proteins, and organization of organelles. It is composed of two antiparallel dimers of alpha- and beta- subunits. SPTBN4, also called beta-IV spectrin, or spectrin, non-erythroid beta chain 3 (SPTBN3), is a novel spectrin isolated as an interactor of the receptor tyrosine phosphatase-like protein ICA512. Its mutation associates with congenital myopathy, neuropathy, and central deafness. SPTBN4 contains two copies of the CH domain. This model corresponds to the first CH domain. CH domains are actin filament (F-actin) binding motifs.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  353 FSDFSDGLILAKLLETV-GEmphgqillKLRDPAGDRIR--KIGNVKIVLQEMSSLGVPTDNVNAESIVGGKKDEILSIL 429
Cdd:cd21318   62 YTDLRDGYVLTRLLEVLsGE--------QLPKPTRGRMRihSLENVDKALQFLKEQRVHLENVGSHDIVDGNHRLTLGLI 133

                 ....
gi 17506033  430 WAII 433
Cdd:cd21318  134 WTII 137

first calponin homology (CH) domain found in the filamin family; The filamin family includes filamin-A (FLN-A), filamin-B (FLN-B) and filamin-C (FLN-C). Filamins function to anchor various transmembrane proteins to the actin cytoskeleton. FLN-A is also called actin-binding protein 280 (ABP-280), alpha-filamin, endothelial actin-binding protein, filamin-1, or non-muscle filamin. It promotes orthogonal branching of actin filaments and links actin filaments to membrane glycoproteins. It also serves as a scaffold for a wide range of cytoplasmic signaling proteins. FLN-B is also called ABP-278, ABP-280 homolog, actin-binding-like protein, beta-filamin, filamin homolog 1 (Fh1), filamin-3, thyroid autoantigen, truncated actin-binding protein, or truncated ABP. It connects cell membrane constituents to the actin cytoskeleton and may also promote orthogonal branching of actin filaments as well as link actin filaments to membrane glycoproteins. FLN-C, also called FLNc, ABP-280-like protein, ABP-L, actin-binding-like protein, filamin-2, or gamma-filamin, is a muscle-specific filamin that plays a central role in muscle cells, probably by functioning as a large actin-cross-linking protein. It may be involved in reorganizing the actin cytoskeleton in response to signaling events, and may also display structural functions at the Z lines in muscle cells. FLN-C is critical for normal myogenesis and for maintaining the structural integrity of the muscle fibers. This family also includes Drosophila melanogaster protein jitterbug (Jbug), which is an actin-meshwork organizing protein containing three copies of the CH domain. Other members of this family contain two copies of the CH domain. This model corresponds to the first CH domain. CH domains are actin filament (F-actin) binding motifs.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  353 FSDFSDGLILAKLLETVGEMP-HGQILLKLRDPAgdriRKIGNVKIVLQEMSSLGVPTDNVNAESIVGGKKDEILSILWA 431
Cdd:cd21183   28 ATDFSDGLCLIALLENLSTRPlKRSYNRRPAFQQ----HYLENVSTALKFIEADHIKLVNIGSGDIVNGNIKLILGLIWT 103

                 ..
gi 17506033  432 II 433
Cdd:cd21183  104 LI 105

first calponin homology (CH) domain found in Saccharomyces cerevisiae fimbrin and similar proteins; Fimbrin binds to actin, and functionally associates with actin structures involved in the development and maintenance of cell polarity. Members of this family contain four copies of the CH domain. This model corresponds to the first CH domain. CH domains are actin filament (F-actin) binding motifs.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  353 FSDFSDGLILAKLL-ETVGEMPHGQILLKLRDP--AGDRIRKIGNVKIVLQEMSSLGVPTDNVNAESIVGGKKDEILSIL 429
Cdd:cd21294   39 FDECKDGLVLSKLInDSVPDTIDERVLNKPPRKnkPLNNFQMIENNNIVINSAKAIGCSVVNIGAGDIIEGREHLILGLI 118

                 ....
gi 17506033  430 WAII 433
Cdd:cd21294  119 WQII 122

first calponin homology (CH) domain found in the dystrophin family; The dystrophin family includes dystrophin and its paralog, utrophin. Dystrophin, encoded by the DMD gene, is a large, submembrane cytoskeletal protein that is the main component of the dystrophin-glycoprotein complex (DGC) in skeletal muscles. It links the transmembrane DGC to the actin cytoskeleton through binding strongly to the cytoplasmic tail of beta-dystroglycan, the transmembrane subunit of a highly O-glycosylated cell-surface protein. Dystrophin is also involved in maintaining the structural integrity of cells, as well as in the formation of the blood-brain barrier (BBB). Utrophin, also called dystrophin-related protein 1 (DRP-1), is an autosomal dystrophin homolog that increases dystrophic muscle function and reduces pathology. It is broadly expressed in both the mRNA and protein levels, and occurs in the cerebrovascular endothelium. Utrophin forms the utrophin-glycoprotein complex (UGC) by interacting with dystroglycans (DGs) and sarcoglycan-dystroglycans, as well as sarcoglycan and sarcospan (SG-SSPN) subcomplexes. It may act as a scaffolding protein that stabilizes lipid microdomains and clusters mechanosensitive channel subunits, and links the F-actin cytoskeleton to the cell membrane via the associated glycoprotein complex. Members of this family contain two copies of the CH domain. This model corresponds to the first CH domain. CH domains are actin filament (F-actin) binding motifs.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17506033  353 FSDFSDGLILAKLLETVGEmphgqilLKLRDPAGD-RIRKIGNVKIVLQEMSSLGVPTDNVNAESIVGGKKDEILSILWA 431
Cdd:cd21186   27 FEDLRDGTRLLALLEVLTG-------KKLKPEKGRmRVHHLNNVNRALQVLEQNNVKLVNISSNDIVDGNPKLTLGLVWS 99

                 ..
gi 17506033  432 II 433
Cdd:cd21186  100 II 101