A protein from CRISPR-Cas Transposase is featured in a series of Foldit puzzles.
The puzzles in this series have included:
- Puzzle 1784: CRISPR-Cas Transposase Part I (Puzzle 1784 results)
- Puzzle 1787: CRISPR-Cas Transposase Part II (Puzzle 1787 results)
- Puzzle 1794: CRISPR-Cas Transposase Part I: Electron Density (Puzzle 1794 results)
These puzzles are larger and more complex than many Foldit puzzles, so some definitions may be useful.
CRISPR is a type of DNA sequence found in bacteria and archaea (prokaryotes). CRISPR sequences are derived from the DNA of bacteriophages, viruses that attack bacteria. CRISPR is in effect part of the immune system of bacteria and archaea.
("CRISPR" stands for "clustered regularly interspaced short palindromic repeats", describing the unusual structure of the DNA sequences.)
CRISPR-Cas in an enzyme that uses CRISPR. ("Cas" is shorthand for "CRISPR-associated" protein.) One CRIPSR-associated protein, known as Cas9 is of particular interest, since it can used for genetic editing of any type of organism, include eukaryotes.
CRISPR gene editing is now the focus of intensive research. Beyond the laboratory, the technique may have many applications in medicine and agriculture.
While CRISPR-Cas is already well-known and widely used, the focus of the Foldit puzzles is the "transposase" in the puzzle titles. A tranposase in an enyzme than can move a section of DNA from section of the genome to another. The Foldit puzzles in the CRISPR-Cas Transposase series involve a "transposition protein" known as TniQ, part of the overall transposase structure.
Because TniQ consists of over 350 residues (segments), which is large for Foldit, the puzzles to date in this series have included roughly half the protein. (See TniQ part 1 and TniQ part 2 for the details on each half.)
Using JPred, the proteins in the Foldit puzzles have matched these PDB entries:
The Foldit proteins partially match chains I and J of these PDB entries. (JPred did not find any other PDB matches.)
The PDB entries were created by a team from Columbia University, and accompany a paper published in Nature, on 18 December, 2019.
The online publication Genetic Engineering and Biotechnology news offers an article describing the CRISPR-Cas TniQ results from the Columbia team. The Nature article's abstract is available on PubMed, but a subscription or one-time purchase is required to view the full text.