EC Number | Activating Compound | Comment | Organism | Structure |
---|---|---|---|---|
3.6.4.13 | RNA | Aquarius hydrolyzes ATP, and this activity is highly stimulated in the presence of a 22-nt RNA with a random sequence. Aquarius does not bind a blunt-ended RNA duplex, and correspondingly the latter does not stimulate Aquarius's ATPase activity | Homo sapiens |
EC Number | Crystallization (Comment) | Organism |
---|---|---|
3.6.4.13 | purified recombinant enzyme Aquanrius, X-ray diffraction structure determination and analysis at 2.3 A resolution | Homo sapiens |
EC Number | Protein Variants | Comment | Organism |
---|---|---|---|
3.6.4.13 | K829A | site-directed mutagenesis, mutation of the invariant lysine residue from motif I involved in ATP binding and hydrolysis drastically reduced Aquarius's ability to bind ATP and ADP and to hydroxadlyze ATP, the mutant shows significantly reduced ATPase activity compared to wild-type enzyme | Homo sapiens |
3.6.4.13 | Y1196A | site-directed mutagenesis, mutation of a conserved aromatic residue located near the putative RNA-binding surface of the RecA2 inhibits Aquarius's RNA-unwinding activity without changing its RNA-binding and ATPase properties, a helicase-deficient mutant | Homo sapiens |
EC Number | Inhibitors | Comment | Organism | Structure |
---|---|---|---|---|
3.6.4.13 | AMP-PNP | structure of Aquarius in complex with AMP-PNP, modelling, overview | Homo sapiens |
EC Number | Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|---|
3.6.4.13 | nucleus | - |
Homo sapiens | 5634 | - |
EC Number | Metals/Ions | Comment | Organism | Structure |
---|---|---|---|---|
3.6.4.13 | Mg2+ | required | Homo sapiens |
EC Number | Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
3.6.4.13 | ATP + H2O | Homo sapiens | - |
ADP + phosphate | - |
? | |
3.6.4.13 | additional information | Homo sapiens | multiple cross-links between Aquarius and hSyf1, hIsy1, CCDC16 or CypE, with the majority of the cross-linked residues located in domains or structural insertions specific for Aquarius, such as the ARM, pointer and thumb domains, and in the large insertions of the beta-barrel | ? | - |
- |
EC Number | Organism | UniProt | Comment | Textmining |
---|---|---|---|---|
3.6.4.13 | Homo sapiens | O60306 | - |
- |
EC Number | Source Tissue | Comment | Organism | Textmining |
---|---|---|---|---|
3.6.4.13 | HeLa cell | - |
Homo sapiens | - |
EC Number | Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
3.6.4.13 | ATP + H2O | - |
Homo sapiens | ADP + phosphate | - |
? | |
3.6.4.13 | additional information | multiple cross-links between Aquarius and hSyf1, hIsy1, CCDC16 or CypE, with the majority of the cross-linked residues located in domains or structural insertions specific for Aquarius, such as the ARM, pointer and thumb domains, and in the large insertions of the beta-barrel | Homo sapiens | ? | - |
- |
|
3.6.4.13 | additional information | Aquarius exhibits ATPase and RNA-unwinding activity in vitro. Consistently with its possessing a Q motif and thus specifically binding ATP, Aquarius does not hydrolyze GT. Aquarius does not bind a blunt-ended RNA duplex | Homo sapiens | ? | - |
- |
EC Number | Subunits | Comment | Organism |
---|---|---|---|
3.6.4.13 | More | enzyme Aquarius is integrated into the spliceosome as part of the intron-binding complex (IBC). The ARM domain is essential for IBC formation | Homo sapiens |
3.6.4.13 | pentamer | - |
Homo sapiens |
EC Number | Synonyms | Comment | Organism |
---|---|---|---|
3.6.4.13 | Aquarius | - |
Homo sapiens |
3.6.4.13 | DExH/D-box RNA helicase | - |
Homo sapiens |
3.6.4.13 | IBP160 | - |
Homo sapiens |
3.6.4.13 | intron-binding protein 160 | - |
Homo sapiens |
3.6.4.13 | RNA helicase Aquarius | - |
Homo sapiens |
EC Number | General Information | Comment | Organism |
---|---|---|---|
3.6.4.13 | malfunction | an ATPase-deficient Aquarius mutant hinders splicing | Homo sapiens |
3.6.4.13 | metabolism | the spliceosome's structural rearrangements are driven by eight conserved DExH/D-box RNA helicases that contain two RecA-like domains, which form a motor module required for ATP hydrolysis, RNA unwinding and coupling of these two processes. RNA helixadcases can have very diverse functions, including proofreading specific steps of pre-mRNA splicing. Most helicases also conxadtain specific accessory domains important for their regulation or task-specific function. The human spliceosome contains five addixadtional RNA helicases (Aquarius, SF3b125, elFAIII and DDX35 and Abstrakt). Multiple cross-links between Aquarius and hSyf1, hIsy1, CCDC16 or CypE, with the majority of the cross-linked residues located in domains or structural insertions specific for Aquarius, such as the ARM, pointer and thumb domains, and in the large insertions of the beta-barrel. The for intron-binding complex (IBC) is cross-linked to U2 SF3a and SF3b proteins, interaction partners of the IBC in the spliceosome. The Aquarius ARM domain is cross-linked to SF3b155 | Homo sapiens |
3.6.4.13 | additional information | the SF1 core of Aquarius consists of two RecA-like domains, an alpha-helical stalk and a beta-barrel domain. The canonical sequence motifs of RNA helicases are conserved, and the ATP analogue binds with the adenine sandwiched between Leu1157 and Ile800. The amino group of the adenine is recognized by Gln806 from the Q motif, a distinctive feature of helicases able to use only ATP. The space between the RecA1, RecA2, beta-barrel and a domain that we denote as an armadillo (ARM) domain is filled by the so-called stalk, a structural unit encompassing 125 residues (416-492 and 660-710) exhibiting helixadces, extensive coils and loops. The large surfaces that the stalk shares with other domains suggest that it has a key architectural role. Notably, numerous large hydrophobic residues that mediate these contacts are highly conxadserved. Aquarius's ARM domain is required for intron-binding complex (IBC) formation | Homo sapiens |
3.6.4.13 | physiological function | RNA helicase Aquarius is crucial for the assembly of box C and box D (box C/D) small nucleolar RNPs (snoRNPs), whose small nucleolar RNAs (snoRNAs) are found in introns about 50 nt upstream of the BS, i.e., 10 nt upstream of Aquarius's binding site. The ATP hydrolysis by Aquarius is required for efficient pre-mRNA splicing | Homo sapiens |