PCNA complex
Definition
Target type: cellularcomponent
A protein complex composed of three identical PCNA monomers, each comprising two similar domains, which are joined in a head-to-tail arrangement to form a homotrimer. Forms a ring-like structure in solution, with a central hole sufficiently large to accommodate the double helix of DNA. Originally characterized as a DNA sliding clamp for replicative DNA polymerases and as an essential component of the replisome, and has also been shown to be involved in other processes including Okazaki fragment processing, DNA repair, translesion DNA synthesis, DNA methylation, chromatin remodeling and cell cycle regulation. [GOC:jl, PMID:12829735]
The PCNA (Proliferating Cell Nuclear Antigen) complex is a ring-shaped heterotrimer composed of three identical PCNA subunits. Each subunit is approximately 29 kDa in size and contains a conserved eight-amino acid motif known as the PIP box. The PCNA complex functions as a processivity factor for DNA polymerases, increasing their efficiency by preventing them from dissociating from the DNA template during replication. It encircles the DNA duplex, creating a central channel through which the polymerase can access the template strand. The complex interacts with various proteins involved in DNA replication, repair, and cell cycle regulation, including DNA polymerases, helicases, and ligases. It forms a stable ring structure that facilitates the coordinated action of these proteins, ensuring efficient and accurate DNA processing.'
"
Proteins (1)
| Protein | Definition | Taxonomy |
|---|---|---|
| Proliferating cell nuclear antigen | A proliferating cell nuclear antigen that is encoded in the genome of human. [PRO:DNx] | Homo sapiens (human) |
Compounds (7)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| 3,3',5-triiodothyroacetic acid | tiratricol : A monocarboxylic acid that is (4-hydroxy-3,5-diiodophenyl)acetic acid in which the phenolic hydroxy group has been replaced by a 4-hydroxy-3-iodophenoxy group. It is a thyroid hormone analogue that has been used in the treatment of thyroid hormone resistance syndrome. | ||
| 3,3',5-triiodothyropropionic acid | aromatic ether | ||
| thyroxine | thyroxine : An iodothyronine compound having iodo substituents at the 3-, 3'-, 5- and 5'-positions. Thyroxine: The major hormone derived from the thyroid gland. Thyroxine is synthesized via the iodination of tyrosines (MONOIODOTYROSINE) and the coupling of iodotyrosines (DIIODOTYROSINE) in the THYROGLOBULIN. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form TRIIODOTHYRONINE which exerts a broad spectrum of stimulatory effects on cell metabolism. | 2-halophenol; iodophenol; L-phenylalanine derivative; non-proteinogenic L-alpha-amino acid; thyroxine; thyroxine zwitterion | antithyroid drug; human metabolite; mouse metabolite; thyroid hormone |
| triiodothyronine | 3,3',5-triiodo-L-thyronine : An iodothyronine compound having iodo substituents at the 3-, 3'- and 5-positions. Although some is produced in the thyroid, most of the 3,3',5-triiodo-L-thyronine in the body is generated by mono-deiodination of L-thyroxine in the peripheral tissues. Its metabolic activity is about 3 to 5 times that of L-thyroxine. The sodium salt is used in the treatment of hypothyroidism. Triiodothyronine: A T3 thyroid hormone normally synthesized and secreted by the thyroid gland in much smaller quantities than thyroxine (T4). Most T3 is derived from peripheral monodeiodination of T4 at the 5' position of the outer ring of the iodothyronine nucleus. The hormone finally delivered and used by the tissues is mainly T3. | 2-halophenol; amino acid zwitterion; iodophenol; iodothyronine | human metabolite; mouse metabolite; thyroid hormone |
| 3,5-diiodothyronine, (l)-isomer | phenylalanine derivative | ||
| 3,3'-diiodothyronine | 3,3'-diiodothyronine: RN given refers to unlabeled cpd without isomeric designation | 3,3'-diiodothyronine; amino acid zwitterion | human metabolite |
| 3,5-diiodothyropropionic acid | 3,5-diiodothyropropionic acid : A monocarboxylic acid that is (4-hydroxy-3,5-diiodophenyl)propanoic acid in which the phenolic hydroxy group has been replaced by a 4-hydroxyphenyl group. An ionotropic analogue of L-thyroxine. 3,5-diiodothyropropionic acid: a cardiotonic thyroid hormone analog | aromatic ether; monocarboxylic acid; organoiodine compound; phenols |