Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.

[Q]: The SET domain contains the catalytic center of lysine methyltransferases that target the N-terminal tails of histones and regulate chromatin function. Here we report the structure of the SET7/9 protein in the absence and presence of its cofactor product, S-adenosyl-L-homocysteine (AdoHcy). A knot within the SET domain helps form the methyltransferase active site, where AdoHcy binds and lysine methylation is likely to occur. A structure-guided comparison of sequences within the SET protein family suggests that the knot substructure and active site environment are conserved features of the SET domain.
[A]: What is the characteristic domain of histone methyltransferases?


[Q]: This article explains what methicillin-resistant Staphylococcus aureus (MRSA) is, how it is spread and what the real challenges are in healthcare settings in the UK. It explores the different strains of MRSA and points out the main ways to control their spread. It is intended to be a reference source for all nurses.
[A]: What is MRSA?


[Q]: Remo Giazotto (September 4, 1910, Rome -- August 26, 1998, Pisa) was an Italian musicologist, music critic, and composer, mostly known through his systematic catalogue of the works of Tomaso Albinoni.
[A]:
The nationality of Remo Giazotto is what?


