AP-3 adaptor complex binding
Definition
Target type: molecularfunction
Binding to an AP-3 adaptor complex. The AP-3 adaptor complex is a heterotetrameric AP-type membrane coat adaptor complex that consists of beta3, delta, mu3 and sigma3 subunits and is found associated with endosomal membranes. In at least humans, the AP-3 complex can be heterogeneric due to the existence of multiple subunit isoforms encoded by different genes (beta3A and beta3B, mu3A and mu3B, and sigma3A and sigma3B). [PMID:21097499]
The AP-3 adaptor complex plays a crucial role in the trafficking of cargo proteins from the trans-Golgi network (TGN) to specific cellular destinations, primarily lysosomes and related compartments. Its molecular function can be described as follows:
1. **Cargo Recognition and Binding:** AP-3 recognizes and binds to specific sorting signals present on cargo proteins. These signals are typically short amino acid sequences, often located within the cytosolic tail of the cargo protein.
2. **Clathrin Coat Assembly:** Once bound to cargo, AP-3 recruits clathrin, a protein that forms a cage-like structure around the budding vesicle. This clathrin coat provides structural support and facilitates the formation of the vesicle.
3. **Vesicle Budding:** The clathrin-coated vesicle containing the cargo protein buds off from the TGN membrane. This budding process is driven by the interaction of AP-3 with other proteins involved in vesicle formation, such as dynamin.
4. **Delivery to Lysosomes:** The AP-3-mediated vesicles then transport the cargo proteins to the lysosomes, where they undergo degradation or other processing events.
5. **Specific Cargo Selection:** AP-3 exhibits selectivity in its cargo binding, ensuring that only specific proteins are sorted to lysosomes. This selectivity is achieved through the recognition of distinct sorting signals on different cargo proteins.
Overall, the molecular function of AP-3 adaptor complex binding involves cargo recognition, clathrin coat assembly, vesicle budding, and targeted delivery of specific proteins to lysosomes. These processes are essential for maintaining cellular homeostasis and regulating diverse cellular functions.'
"
Proteins (1)
| Protein | Definition | Taxonomy |
|---|---|---|
| Phosphatidylinositol 4-kinase type 2-alpha | A phosphatidylinositol 4-kinase type 2-alpha that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q9BTU6] | Homo sapiens (human) |
Compounds (14)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| 9-ethyladenine | |||
| n(6),n(6)-dimethyladenine | N(6),N(6)-dimethyladenine : A tertiary amine that is adenine substituted at N-6 by geminal methyl groups. | tertiary amine | |
| 1-phenyl-4-pyrazolo[3,4-d]pyrimidinamine | pyrazoles; ring assembly | ||
| sq 22536 | 9-(tetrahydrofuryl)adenine : A nucleoside analogue that is adenine in which the nitrogen at position 9 has been substituted by a tetrahydrofuran-2-yl group. It is an adenylate cyclase inhibitor. | nucleoside analogue; oxolanes | EC 4.6.1.1 (adenylate cyclase) inhibitor |
| adenosine diphosphate | Adenosine Diphosphate: Adenosine 5'-(trihydrogen diphosphate). An adenine nucleotide containing two phosphate groups esterified to the sugar moiety at the 5'-position. | adenosine 5'-phosphate; purine ribonucleoside 5'-diphosphate | fundamental metabolite; human metabolite |
| 2-aminopurine | 2-aminopurine : The parent compound of the 2-aminopurines, comprising a purine core carrying an amino substituent at the 2-position. 2-Aminopurine: A purine that is an isomer of ADENINE (6-aminopurine). aminopurine : Any purine having at least one amino substituent. | 2-aminopurines; nucleobase analogue | antimetabolite |
| alpha-aminopyridine | alpha-aminopyridine: RN given refers to parent cpd; structure in Merck Index, 9th ed, #485 aminopyridine : Compounds containing a pyridine skeleton substituted by one or more amine groups. | ||
| 9-benzyladenine | |||
| adenosine | quinquefolan B: isolated from roots of Panax quinquefolium L.; RN not in Chemline 10/87; RN from Toxlit | adenosines; purines D-ribonucleoside | analgesic; anti-arrhythmia drug; fundamental metabolite; human metabolite; vasodilator agent |
| benzylaminopurine | benzylaminopurine: a plant growth regulator N-benzyladenine : A member of the class of 6-aminopurines that is adenine in which one of the hydrogens of the amino group is replaced by a benzyl group. | 6-aminopurines | cytokinin; plant metabolite |
| 9-methyladenine | 9-methyladenine : Adenine substituted with a methyl group at position N-9. | methyladenine | metabolite |
| 4-aminopyrazolo(3,4-d)pyrimidine | 4-aminopyrazolo(3,4-d)pyrimidine: adenine analog which suppresses growth of E coli & Bacillus cereus; inhibits cell growth & purine biosynthesis in rat hepatoma | ||
| 4-aminoquinazoline | 4-aminoquinazoline: structure in first source | ||
| wortmannin | acetate ester; cyclic ketone; delta-lactone; organic heteropentacyclic compound | anticoronaviral agent; antineoplastic agent; autophagy inhibitor; EC 2.7.1.137 (phosphatidylinositol 3-kinase) inhibitor; geroprotector; Penicillium metabolite; radiosensitizing agent |