1j5u

Protein Summary

The TM1083 gene from Thermotoga maritima encodes a protein of unkown function (DUF101 (PF01951), COG1371). The family has a wide phylogenetic distribution, encountered in archaea, viruses, fungi, insects (moth, mosquito, fruit fly), nematodes, fish and mammals including humans. The TM1083 structure adopts a novel fold termed MTH1598-like fold and shows strong similarity (2.6 Å main-chain rmsd over 112 residues with 20% sequence identity; Dali Zscr=10) to another DUF101 homolog from Methanothermobacter thermoautotrophicus (PDB id: 1jw3) from which the fold takes its name. Both structures comprise a single domain with two helices in the center flanked by short beta-sheets at both ends. This arrangement is reminiscent of BTB/POZ domains which have been described in a wide range of organisms as protein-protein interactions modules (Perez-Torrado 2006) with a role in the regulation of DNA transcription. Structural analysis of 1jw3 shows similarity to heat-shock protein 33 (PDB id: 1i7f; Dali Z=4) and suggests a function in RNA binding (Yee 2002) with bioinformatics analysis predicting a role as chaperone or modulators of proteins involved in DNA or RNA processing (Canaves 2004).

The genetic neighborhood of TM1083 shows with a high probability a functional association with a LexA repressor (EC 3.4.21.88), DNA gyrase subunit A (EC 5.99.1.3), a putative anti-sigma factor antagonist (TM1081), a methionyl-tRNA synthetase (EC 6.1.1.10) and a ribosomal protein L11 methyltransferase, suggesting an involvement in regulation of DNA transcription. A similar neighborhood is observed for MTH1598 and shows cooccurrence with a DNA polymerase sliding clamp.

RNA interference experiments have shown the C. elegans DUF101 homolog to be implicated in larval arrest and genitalia development. Yeast-two-hybrid experiments in the D. melanogaster DUF101 homolog have shown physical interactions with a stress-response chaperone (DnaJ-1), proteins involved in translation-elongation and ribosomes (Ef1-gamma, RpS7, SnrB) and a protein located on the germline ring canal involved in germ-line cyst encapsulation (cher).

[Any data on whether or not 1j5u forms a dimer in solution?]

[electrostatics? look for hydrophobic patch that might indicate area of protein-protein interactions]

[Describe structural differences between 1j5u and 1jw3, including conformational change in the presence of calcium.]

Ligand Summary

References