Calponin homology domain (or CH domain) is a family of

actin Actin is a family of globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in muscle fibrils. It is found in essentially all eukaryotic cells, where it may be present at a concentration of ...

binding domains found in both cytoskeletal proteins and signal transduction proteins. The domain is about 100 amino acids in length and is composed of four alpha helices. It comprises the following groups of actin-binding domains: *

Actinin Actinin is a microfilament protein. The functional protein is an anti-parallel dimer, which cross-links the thin filaments in adjacent sarcomeres, and therefore coordinates contractions between sarcomeres in the horizontal axis. Alpha-actinin is ...

-type (including spectrin, fimbrin, ABP-280) *

Calponin Calponin is a calcium binding protein. Calponin tonically inhibits the ATPase activity of myosin in smooth muscle. Phosphorylation of calponin by a protein kinase, which is dependent upon calcium binding to calmodulin, releases the calponin's ...

-type A comprehensive review of proteins containing this type of actin-binding domains is given in. 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 proteins have two copies of the CH domain, however some proteins such as calponin and the human vav proto-oncogene () have only a single copy. The structure of an example CH domain has been determined using

X-ray crystallography X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring th ...

Examples

Human genes encoding calponin homology domain-containing proteins include: *

ACTN1 Alpha-actinin-1 is a protein that in humans is encoded by the ''ACTN1'' gene. Function Alpha actinins belong to the spectrin gene superfamily which represents a diverse group of cytoskeleton, cytoskeletal proteins, including the alpha and bet ...

ACTN2 Alpha-actinin-2 is a protein which in humans is encoded by the ''ACTN2'' gene. This gene encodes an alpha-actinin isoform that is expressed in both skeletal and cardiac muscles and functions to anchor myofibrillar actin thin filaments and titin to ...

ACTN3 Alpha-actinin-3, also known as alpha-actinin skeletal muscle isoform 3 or F-actin cross-linking protein, is a protein that in humans is encoded by the ''ACTN3'' gene (named sprinter gene, speed gene or athlete gene) located on chromosome 11. All ...

ACTN4 Alpha-actinin-4 is a protein that in humans is encoded by the ''ACTN4'' gene. Alpha actinins belong to the spectrin gene superfamily which represents a diverse group of cytoskeletal proteins, including the alpha and beta spectrins and dystrophin ...

, ARHGEF6,

ARHGEF7 Rho guanine nucleotide exchange factor 7 is a protein that in humans is encoded by the ''ARHGEF7'' gene. ARHGEF7 is commonly known as the p21-activated protein kinase exchange factor beta (beta-PIX or βPIX), because it was identified by binding ...

, ASPM, * CLMN,

CNN1 Calponin 1 is a basic smooth muscle protein that in humans is encoded by the ''CNN1'' gene. The ''CNN1'' gene is located at 19p13.2-p13.1 in the human chromosomal genome and contains 7 exons, encoding the protein calponin 1, an actin filament-ass ...

CNN2 Calponin 2 is a protein that in humans is encoded by the ''CNN2'' gene. The ''CNN2'' gene is located at 19p13.3 in the human chromosomal genome, encoding the protein calponin 2. Calponin 2 is one of the three isoforms of calponin and an actin fi ...

, CNN3, * DIXDC1, DMD,

DST Daylight saving time (DST), also referred to as daylight savings time, daylight time (United States and Canada), or summer time (United Kingdom, European Union, and others), is the practice of advancing clocks to make better use of the long ...

, * EHBP1, EHBP1L1, *

FLNA Filamin A, alpha (FLNA) is a protein that in humans is encoded by the ''FLNA'' gene. Structure The structure of Filamin A, alpha includes an actin binding N terminal domain, 24 internal repeats and 2 hinge regions. Function Actin-binding p ...

FLNB Filamin B, beta (FLNB), also known as Filamin B, beta (truncated actin binding protein 278 homolog), is a cytoplasmic protein which in humans is encoded by the ''FLNB'' gene. FLNB regulates intracellular communication and signalling by cross-link ...

, FLNC, * GAS2, GAS2L1, GAS2L2, GAS2L3, *

IQGAP1 Ras GTPase-activating-like protein IQGAP1 (IQGAP1) also known as p195 is a ubiquitously expressed protein that in humans is encoded by the ''IQGAP1'' gene. IQGAP1 is a scaffold protein involved in regulating various cellular processes ranging fro ...

, IQGAP2, IQGAP3, *

LCP1 Plastin-2 is a protein that in humans is encoded by the ''LCP1'' gene. Function Plastins are a family of actin-binding proteins that are conserved throughout eukaryote evolution and expressed in most tissues of higher eukaryotes. In humans, t ...

, LIMCH1, LMO7, LRCH1, LRCH2, LRCH3, LRCH4, *

MACF1 Microtubule-actin cross-linking factor 1, isoforms 1/2/3/5 is a protein that in humans is encoded by the ''MACF1'' gene. MACF1 encodes a large protein containing numerous spectrin and leucine-rich repeat (LRR) domains. MACF1 is a member of a fami ...

MAPRE1 Microtubule-associated protein RP/EB family member 1 is a protein that in humans is encoded by the ''MAPRE1'' gene. Function The protein encoded by this gene was first identified by its binding to the APC (Adenomatous polyposis coli) protein ...

MAPRE2 Microtubule-associated protein RP/EB family member 2 is a protein that in humans is encoded by the ''MAPRE2'' gene. Function The protein encoded by this gene shares significant homology to the adenomatous polyposis coli (APC) protein-binding ...

MAPRE3 Microtubule-associated protein RP/EB family member 3 is a protein that in humans is encoded by the ''MAPRE3'' gene. The protein encoded by this gene is a member of the RP/EB family of genes. The protein localizes to the cytoplasmic microtubule ...

MICAL1 NEDD9-interacting protein with calponin homology and LIM domains is a protein that in humans is encoded by the ''MICAL1'' gene. Interactions MICAL1 has been shown to Protein-protein interaction, interact with NEDD9 and RAB1A. References Furthe ...

MICAL2 Protein MICAL-2 is a protein that in humans is encoded by the ''MICAL2'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcr ...

MICAL2PV1 MICAL may refer to: * MICAL1, protein * MICAL2, protein * MICAL3, protein * MICALL1, protein * MICAL (Bahamas Parliament constituency) {{Disambiguation Acronyms ...

MICAL2PV2 MICAL may refer to: * MICAL1 NEDD9-interacting protein with calponin homology and LIM domains is a protein that in humans is encoded by the ''MICAL1'' gene. Interactions MICAL1 has been shown to Protein-protein interaction, interact with NEDD9 a ...

MICAL3 Microtubule-associated monoxygenase, calponin and LIM domain containing 3, also known as MICAL3, is a human gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence o ...

MICALL1 MICAL-like 1, also known as MICALL1, is a human gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functi ...

, MICALL2, * NAV2, NAV3, *

PARVA Alpha-parvin is a protein that in humans is encoded by the ''PARVA'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcrib ...

PARVB Beta-parvin is a protein that in humans is encoded by the ''PARVB'' gene. Members of the parvin family, including PARVB, PARVA Alpha-parvin is a protein that in humans is encoded by the ''PARVA'' gene In biology, the word gene has two ...

, PARVG,

PLEC1 Plectin is a giant protein found in nearly all mammalian cells which acts as a link between the three main components of the cytoskeleton: actin microfilaments, microtubules and intermediate filaments. In addition, plectin links the cytoskeleton ...

PLS1 Fimbrin also known as is plastin 1 is a protein that in humans is encoded by the PLS1 gene. Fimbrin is an actin cross-linking protein important in the formation of filopodia. Structure Fimbrin belongs to the calponin homology (biology), homolo ...

, PLS3, PP14183, * SMTN, SMTNL2, SPECC1, SPECC1L, SPNB4, SPTB,

SPTBN1 Spectrin beta chain, brain 1 is a protein that in humans is encoded by the ''SPTBN1'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA th ...

SPTBN2 Spectrin beta chain, brain 2 is a protein that in humans is encoded by the ''SPTBN2'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA th ...

, SPTBN4, SPTBN5,

SYNE1 Enaptin also known as nesprin-1 or synaptic nuclear envelope protein 1 (syne-1) is an actin-binding protein that in humans that is encoded by the SYNE1 gene. Function This gene encodes a spectrin repeat containing protein expressed in skeletal ...

SYNE2 Nesprin-2 is a protein that in humans is encoded by the ''SYNE2'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed t ...

, * TAGLN, TAGLN2, TAGLN3, * UTRN, and *

VAV1 Proto-oncogene vav is a protein that in humans is encoded by the ''VAV1'' gene. Function The protein encoded by this proto-oncogene is a member of the Dbl family of guanine nucleotide exchange factors (GEF) for the Rho family of GTP binding ...

, VAV2,

VAV3 Guanine nucleotide exchange factor VAV3 is a protein that in humans is encoded by the ''VAV3'' gene. This gene is a member of the VAV gene family. The VAV proteins are guanine nucleotide exchange factors (GEFs) for Rho family GTPases that activ ...

References

{{InterPro content, IPR001715 Protein domains