C1 domain (also known as phorbol esters/diacylglycerol binding domain) binds an important secondary messenger

diacylglycerol A diglyceride, or diacylglycerol (DAG), is a glyceride consisting of two fatty acid chains covalently bonded to a glycerol molecule through ester linkages. Two possible forms exist, 1,2-diacylglycerols and 1,3-diacylglycerols. DAGs can act as sur ...

(DAG), as well as the analogous phorbol esters. Phorbol esters can directly stimulate

protein kinase C In cell biology, Protein kinase C, commonly abbreviated to PKC (EC 2.7.11.13), is a family of protein kinase enzymes that are involved in controlling the function of other proteins through the phosphorylation of hydroxyl groups of serine and ...

, PKC. Phorbol esters (such as PMA) are analogues of DAG and potent

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

promoters that cause a variety of physiological changes when administered to both cells and tissues. DAG activates a family of

serine/threonine protein kinase A serine/threonine protein kinase () is a kinase enzyme, in particular a protein kinase, that phosphorylates the OH group of the amino-acid residues serine or threonine, which have similar side chains. At least 350 of the 500+ human prote ...

s, collectively known as

(PKC). Phorbol esters can directly stimulate PKC. The

N-terminal The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the amin ...

region of PKC, known as C1, binds PMA and DAG in a

phospholipid Phospholipids, are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). Marine phospholipids ty ...

and zinc-dependent fashion. The C1 region contains one or two copies of a cysteine-rich domain, which is about 50 amino-acid residues long, and which is essential for DAG/PMA-binding. The DAG/PMA-binding domain binds two zinc ions; the ligands of these metal ions are probably the six cysteines and two histidines that are conserved in this domain.

Human proteins containing this domain

AKAP13 A-kinase anchor protein 13 is a protein that in humans is encoded by the ''AKAP13'' gene. This protein is also called AKAP-Lbc because it encodes the lymphocyte blast crisis (Lbc) oncogene, and ARHGEF13/RhoGEF13 because it contains a guanine nucle ...

;

ARAF Serine/threonine-protein kinase A-Raf or simply A-Raf is an enzyme that in humans is encoded by the ''ARAF'' gene. A-Raf is a member of the Raf kinase family of serine/threonine-specific protein kinases. Compared to the other members of this ...

; ARHGAP29; ARHGEF2; BRAF; CDC42BPA; CDC42BPB; CDC42BPG; CHN1; CHN2; CIT; CIC;

DGKA Diacylglycerol kinase alpha is an enzyme that in humans is encoded by the ''DGKA'' gene. The protein encoded by this gene belongs to the eukaryotic diacylglycerol kinase family. It acts as a modulator that competes with protein kinase C for the ...

; DGKB; DGKD; DGKE; DGKG; DGKH; DGKI; DGKK; DGKQ; DGKZ; GMIP;

HMHA1 Minor histocompatibility protein HA-1 is a protein that in humans is encoded by the ''HMHA1'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''gen ...

; KSR1; KSR2; MYO9A; MYO9B; PDZD8; PRKCA;

PRKCB1 Protein kinase C beta type is an enzyme that in humans is encoded by the ''PRKCB'' gene. Protein kinase C (PKC) is a family of serine- and threonine-specific protein kinases that can be activated by calcium and second messenger diacylglycerol. PK ...

;

PRKCD Protein kinase C delta type (or PKC-δ) is an enzyme that in humans is encoded by the ''PRKCD'' gene. Function Protein kinase C (PKC) is a family of serine- and threonine-specific protein kinases that can be activated by the second messenge ...

;

PRKCE Protein kinase C epsilon type (PKCε) is an enzyme that in humans is encoded by the ''PRKCE'' gene. PKCε is an isoform of the large PKC family of protein kinases that play many roles in different tissues. In cardiac muscle cells, PKCε regulate ...

;

PRKCG Protein kinase C gamma type is an enzyme that in humans is encoded by the ''PRKCG'' gene. Protein kinase C (PKC) is a family of serine- and threonine-specific protein kinases that can be activated by calcium and second messenger diacylglycerol. ...

; PRKCH;

PRKCI Protein kinase C iota type is an enzyme that in humans is encoded by the ''PRKCI'' gene. Function This gene encodes a member of the protein kinase C (PKC) family of serine/threonine protein kinases. The PKC family comprises at least eight membe ...

; PRKCN;

PRKCQ Protein kinase C theta (PKC-θ) is an enzyme that in humans is encoded by the ''PRKCQ'' gene. PKC-θ, a member of serine/threonine kinases, is mainly expressed in hematopoietic cells with high levels in platelets and T lymphocytes, where plays a ...

; PRKCZ; PRKD1; PRKD2; PRKD3;

RACGAP1 Rac GTPase-activating protein 1 is an enzyme that in humans is encoded by the ''RACGAP1'' gene. Function Rho GTPases control a variety of cellular processes. There are 3 subtypes of Rho GTPases in the Ras superfamily of small G proteins: RHO (s ...

;

RAF1 RAF proto-oncogene serine/threonine-protein kinase, also known as proto-oncogene c-RAF or simply c-Raf or even Raf-1, is an enzyme that in humans is encoded by the ''RAF1'' gene. The c-Raf protein is part of the ERK1/2 pathway as a MAP kinase ...

; RASGRP; RASGRP1;

RASGRP2 RAS guanyl-releasing protein 2 is a protein that in humans is encoded by the ''RASGRP2'' gene. The protein encoded by this gene is a brain-enriched nucleotide exchanged factor that contains an N-terminal GEF domain, 2 tandem repeats of EF-hand cal ...

; RASGRP3;

RASGRP4 RAS guanyl releasing protein 4 is a protein in humans that is encoded by the RASGRP4 gene in chromosome 19. The protein encoded by this gene is a member of the Ras guanyl nucleotide-releasing protein (RasGRP) family of Ras guanine nucleotide exc ...

; RASSF1;

RASSF5 Ras association domain-containing protein 5 is a protein that in humans is encoded by the ''RASSF5 or F5'' gene. Function This gene is a member of the Ras association domain family. It functions as a tumor suppressor, and is inactivated in a va ...

;

ROCK1 ROCK1 is a protein serine/threonine kinase also known as rho-associated, coiled-coil-containing protein kinase 1. Other common names are ROKβ and P160ROCK. ROCK1 is a major downstream effecter of the small GTPase RhoA and is a regulator of the ...

;

ROCK2 Rho associated coiled-coil containing protein kinase 2 is a protein that in humans is encoded by the ROCK2 gene. Fasudil is an inhibitor of ROCK protein. Function The protein encoded by this gene is a serine/threonine kinase that regulates ...

; STAC; STAC2; STAC3; TENC1;

UNC13A Unc-13 homolog A (''C. elegans'') is a protein that in humans is encoded by the UNC13A gene. Function This gene encodes a member of the UNC13 family. UNC13A plays a role in vesicle maturation during exocytosis as a target of the diacylglycerol ...

;

UNC13B Protein unc-13 homolog B is a protein that in humans is encoded by the ''UNC13B'' gene. Function This gene is expressed in the kidney cortical epithelial cells and is upregulated by hyperglycemia. The encoded protein shares a high level of s ...

; UNC13C;

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 pr ...

;

VAV2 Guanine nucleotide exchange factor VAV2 is a protein that in humans is encoded by the ''VAV2'' gene. VAV2 is the second member of the VAV oncogene family. Unlike VAV1, which is expressed exclusively in hematopoietic cells, VAV2 transcripts were f ...

; VAV3;

References

External links

* - Orientations of C1 domains in membranes (OPM) {{DEFAULTSORT:C1 Domain Peripheral membrane proteins Protein domains