This domain can be found in 5' to 3' exoribonuclease 1 (XRN1) which belong to a family of conserved enzymes in eukaryotes and have important functions in transcription, RNA metabolism, and RNA interference. Xrn1 in fungi and animals is primarily cyto ...
This domain can be found in 5' to 3' exoribonuclease 1 (XRN1) which belong to a family of conserved enzymes in eukaryotes and have important functions in transcription, RNA metabolism, and RNA interference. Xrn1 in fungi and animals is primarily cytosolic, involved in degradation of decapped mRNAs, nonsense mediated decay, microRNA decay and is essential for proper development. The Xrn1 homolog in Drosophila, known as Pacman, is required for male fertility [1]. This entry relates to domain 2 and 3 combined which can be found in the 510-residue C-terminal extension found in XRN1 and not in XRN2/Rat1. Domain D2 is formed by two stretches of Xrn1, residues 915-960 and 1134-1151. The presence of domain (D3) is suggested based on structure. This domain is formed by residues 979-1109, in the insert of domain D2. It is suggested that domains D2-D4 may help maintain domain D1 Pfam:PF18332 in the correct conformation, thereby indirectly stabilising the conformation of the N-terminal segment Pfam:PF03159 [1].
This domain can be found in 5' to 3' exoribonuclease 1 (XRN1) which belong to a family of conserved enzymes in eukaryotes and have important functions in transcription, RNA metabolism, and RNA interference. Xrn1 in fungi and animals is primarily cyto ...
This domain can be found in 5' to 3' exoribonuclease 1 (XRN1) which belong to a family of conserved enzymes in eukaryotes and have important functions in transcription, RNA metabolism, and RNA interference. Xrn1 in fungi and animals is primarily cytosolic and is involved in degradation of decapped mRNAs, nonsense mediated decay, microRNA decay and is essential for proper development. The Xrn1 homolog in Drosophila, known as Pacman, is required for male fertility [1]. This domain (D1) along with 3 other domains, make up a 510-residue segment following the conserved regions found in XRNs but they are only present in XRN1 and are absent in Rat1/XRN2. The amino acid sequences of these four domains contain an excess of basic residues, suggesting that these domains might help in binding the RNA substrate. Mutational studies carried out in D1 domain show that the mutant forms had dramatically reduced nuclease activity towards ssDNA substrate indicating that domain D1 is required for Xrn1 nuclease activity [1].
This is the C-terminal SH3-like domain which can be found in the exoribonuclease Xrn1. Xrn1 is a 175 kDa processive exoribonuclease that is conserved from yeast to mammals which targets cytoplasmic RNA substrates marked by a 5' monophosphate for proc ...
This is the C-terminal SH3-like domain which can be found in the exoribonuclease Xrn1. Xrn1 is a 175 kDa processive exoribonuclease that is conserved from yeast to mammals which targets cytoplasmic RNA substrates marked by a 5' monophosphate for processive 5'-to-3' degradation. The Sh3-like domain in Xrn1 lacks the canonical SH3 residues normally involved in binding proline-rich peptide motifs and instead engages in non-canonical interactions with the catalytic domain. Additionally it is essential in maintaining the structural integrity of Xrn1, since partial truncation of this domain in yeast Xrn1 yields an inactive protein. There is a long loop projecting from the SH3-like domain that contacts the PAZ/Tudor domain, occluding the functional surface that binds RNA or peptide motifs containing methylated arginines, respectively, in canonical PAZ and Tudor domain [1].
