RNA 7-methylguanosine cap binding
Definition
Target type: molecularfunction
Binding to a 7-methylguanosine group added cotranscriptionally to the 5' end of RNA molecules transcribed by polymerase II. [GOC:krc]
The 7-methylguanosine (m7G) cap is a unique modification found at the 5' end of eukaryotic messenger RNA (mRNA) molecules. It plays a critical role in the regulation of many fundamental cellular processes, including mRNA stability, translation initiation, and nuclear export. The m7G cap is recognized by a family of proteins known as cap-binding proteins (CBPs), which mediate its diverse functions.
The molecular function of RNA 7-methylguanosine cap binding can be described as follows:
1. **Recognition and Binding:** CBPs specifically recognize and bind to the m7G cap through a conserved cap-binding domain. This interaction is highly specific and provides a molecular basis for distinguishing mRNA from other cellular RNAs.
2. **Protection from Degradation:** The m7G cap protects the 5' end of mRNA from exonucleolytic degradation by 5' to 3' exonucleases. This protective function ensures the integrity and stability of mRNA molecules.
3. **Translation Initiation:** The m7G cap plays a crucial role in translation initiation. It is recognized by the eukaryotic initiation factor 4E (eIF4E), which is a key component of the translation initiation complex. Binding of eIF4E to the m7G cap facilitates the recruitment of the ribosome to the mRNA, thereby initiating protein synthesis.
4. **Nuclear Export:** The m7G cap is essential for the nuclear export of mRNA. It interacts with nuclear export factors, such as the cap-binding complex (CBC), which helps to transport mature mRNA from the nucleus to the cytoplasm, where it can be translated.
5. **mRNA Splicing:** The m7G cap has been implicated in mRNA splicing, the process by which non-coding introns are removed from pre-mRNA to produce mature mRNA.
6. **Regulation of Translation:** The m7G cap can influence the translation efficiency of specific mRNAs, depending on the presence of other regulatory elements within the mRNA sequence.
In summary, the molecular function of RNA 7-methylguanosine cap binding is multifaceted and essential for the proper regulation of gene expression in eukaryotic cells. It governs mRNA stability, translation initiation, nuclear export, and other critical cellular processes. This intricate molecular interaction ensures the efficient and accurate production of proteins from the genetic code.'
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Proteins (3)
| Protein | Definition | Taxonomy |
|---|---|---|
| Protein argonaute-2 | A protein argonaute-2 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q9UKV8] | Homo sapiens (human) |
| m7GpppX diphosphatase | A scavenger mRNA-decapping enzyme DcpS that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q96C86] | Homo sapiens (human) |
| Eukaryotic translation initiation factor 4E | A eukaryotic translation initiation factor 4E that is encoded in the genome of human. [PRO:DNx, UniProtKB:P06730] | Homo sapiens (human) |
Compounds (10)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| sulfaguanidine | sulfaguanidine : A sulfonamide incorporating a guanidine moiety used to block the synthesis of folic acid; mostly used in veterinary medicine Sulfaguanidine: A sulfanilamide antimicrobial agent that is used to treat enteric infections. | sulfonamide antibiotic | antiinfective agent |
| sulfanilamide | substituted aniline; sulfonamide; sulfonamide antibiotic | antibacterial agent; drug allergen; EC 4.2.1.1 (carbonic anhydrase) inhibitor | |
| sulfisomidine | sulfisomidine : A sulfonamide consisting of pyrimidine having methyl substituents at the 2- and 6-positions and a 4-aminobenzenesulfonamido group at the 4-position. Sulfisomidine: A sulfanilamide antibacterial agent. | pyrimidines; sulfonamide; sulfonamide antibiotic | antiinfective agent |
| uridine monophosphate | uridine 5'-monophosphate : A pyrimidine ribonucleoside 5'-monophosphate having uracil as the nucleobase. Uridine Monophosphate: 5'-Uridylic acid. A uracil nucleotide containing one phosphate group esterified to the sugar moiety in the 2', 3' or 5' position. | pyrimidine ribonucleoside 5'-monophosphate; uridine 5'-phosphate | Escherichia coli metabolite; human metabolite; mouse metabolite |
| 2,4-diaminoquinazoline | |||
| sirolimus | sirolimus : A macrolide lactam isolated from Streptomyces hygroscopicus consisting of a 29-membered ring containing 4 trans double bonds, three of which are conjugated. It is an antibiotic, immunosupressive and antineoplastic agent. Sirolimus: A macrolide compound obtained from Streptomyces hygroscopicus that acts by selectively blocking the transcriptional activation of cytokines thereby inhibiting cytokine production. It is bioactive only when bound to IMMUNOPHILINS. Sirolimus is a potent immunosuppressant and possesses both antifungal and antineoplastic properties. | antibiotic antifungal drug; cyclic acetal; cyclic ketone; ether; macrolide lactam; organic heterotricyclic compound; secondary alcohol | antibacterial drug; anticoronaviral agent; antineoplastic agent; bacterial metabolite; geroprotector; immunosuppressive agent; mTOR inhibitor |
| 6-mercapto-7-methylguanosine | 6-mercapto-7-methylguanosine: structure given in first source | ||
| cgp 57380 | CGP 57380: inhibits the mitogen-activated protein kinase-interacting kinase Mnk1 | pyrazolopyrimidine | |
| 5-((1-(2,6-dichlorobenzyl)piperidin-4-yl)methoxy)quinazoline-2,4-diamine | 5-((1-(2,6-dichlorobenzyl)piperidin-4-yl)methoxy)quinazoline-2,4-diamine: inhibits DcpS protein | ||
| 7-methyl-GTP | guanosine 5'-phosphate |