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. Diglycerides are n ...

(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 t ...

, 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 pro ...

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 typ ...

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;

ARAF Serine/threonine-protein kinase A-Raf, or simply A-Raf, is an enzyme that in humans is encoded by the ''ARAF'' gene. It belongs to the Raf kinase family of serine/threonine-specific protein kinases, which also includes Raf-1 and B-Raf. A-Raf is ...

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

CIC CIC may refer to: Organizations Canada * Cadet Instructors Cadre, a part of the Canadian Armed Forces * Canadian Infantry Corps, renamed in 1947 to Royal Canadian Infantry Corps * Canadian International Council * Canadian Islamic Congress * Chemi ...

; DGKA; DGKB; DGKD; DGKE; DGKG; DGKH; DGKI; DGKK; DGKQ; DGKZ; GMIP; HMHA1; 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 messeng ...

;

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 regulat ...

; PRKCG; 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 memb ...

; PRKCN; PRKCQ;

PRKCZ Protein kinase C, zeta (PKCζ), also known as PRKCZ, is a protein in humans that is encoded by the ''PRKCZ'' gene. The PRKCZ gene encodes at least two alternative transcripts, the full-length PKCζ and an N-terminus, N-terminal truncated form P ...

; PRKD1; PRKD2; PRKD3; RACGAP1; RAF1; RASGRP;

RASGRP1 RAS guanyl-releasing protein 1 is a protein that in humans is encoded by the ''RASGRP1'' gene. Function RAS guanyl nucleotide-releasing protein (RASGRP) is a member of a family of genes characterized by the presence of a Ras superfamily guan ...

; RASGRP2;

RASGRP3 Ras guanyl-releasing protein 3 is a protein that in humans is encoded by the ''RASGRP3'' 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 ...

; RASGRP4; RASSF1; RASSF5;

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 effector of the small GTPase RhoA and is a regulator of the ...

; ROCK2; 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 diacylglycero ...

;

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 sim ...

; 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 ...

; 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

External links

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