6CQM

Crystal Structure of mitochondrial single-stranded DNA binding proteins from S. cerevisiae, Rim1 (Form2)

6CQM の概要

• エントリーDOI: 10.2210/pdb6cqm/pdb
• 分子名称: Single-stranded DNA-binding protein RIM1, mitochondrial (1 entity in total)
• 機能のキーワード: mitochondrial single-stranded dna binding proteins, dna binding protein
• 由来する生物種: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast)
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 107486.22

構造登録者

Singh, S.P.,Kukshal, V.,Bona, P.D.,Lytle, A.K.,Edwin, A.,Galletto, R. (登録日: 2018-03-15, 公開日: 2018-05-30, 最終更新日: 2024-03-13)

主引用文献

Singh, S.P.,Kukshal, V.,De Bona, P.,Antony, E.,Galletto, R.
The mitochondrial single-stranded DNA binding protein from S. cerevisiae, Rim1, does not form stable homo-tetramers and binds DNA as a dimer of dimers.
Nucleic Acids Res., 46:7193-7205, 2018

PubMed Abstract: Rim1 is the mitochondrial single-stranded DNA binding protein in Saccharomyces cerevisiae and functions to coordinate replication and maintenance of mtDNA. Rim1 can form homo-tetramers in solution and this species has been assumed to be solely responsible for ssDNA binding. We solved structures of tetrameric Rim1 in two crystals forms which differ in the relative orientation of the dimers within the tetramer. In testing whether the different arrangement of the dimers was due to formation of unstable tetramers, we discovered that while Rim1 forms tetramers at high protein concentration, it dissociates into a smaller oligomeric species at low protein concentrations. A single point mutation at the dimer-dimer interface generates stable dimers and provides support for a dimer-tetramer oligomerization model. The presence of Rim1 dimers in solution becomes evident in DNA binding studies using short ssDNA substrates. However, binding of the first Rim1 dimer is followed by binding of a second dimer, whose affinity depends on the length of the ssDNA. We propose a model where binding of DNA to a dimer of Rim1 induces tetramerization, modulated by the ability of the second dimer to interact with ssDNA.

PubMed: 29931186
DOI: 10.1093/nar/gky530

実験手法

X-RAY DIFFRACTION (3 Å)