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

[EX Q]: The conserved histone variant H2A.Z functions in euchromatin to antagonize the spread of heterochromatin. The mechanism by which histone H2A is replaced by H2A.Z in the nucleosome is unknown. We identified a complex containing 13 different polypeptides associated with a soluble pool of H2A.Z in Saccharomyces cerevisiae. This complex was designated SWR1-Com in reference to the Swr1p subunit, a Swi2/Snf2-paralog. Swr1p and six other subunits were found only in SWR1-Com, whereas six other subunits were also found in the NuA4 histone acetyltransferase and/or the Ino80 chromatin remodeling complex. H2A.Z and SWR1 were essential for viability of cells lacking the EAF1 component of NuA4, pointing to a close functional connection between these two complexes. Strikingly, chromatin immunoprecipitation analysis of cells lacking Swr1p, the presumed ATPase of the complex, revealed a profound defect in the deposition of H2A.Z at euchromatic regions that flank the silent mating type cassette HMR and at 12 other chromosomal sites tested. Consistent with a specialized role for Swr1p in H2A.Z deposition, the majority of the genome-wide transcriptional defects seen in swr1Delta cells were also found in htz1Delta cells. These studies revealed a novel role for a member of the ATP-dependent chromatin remodeling enzyme family in determining the region-specific histone subunit composition of chromatin in vivo and controlling the epigenetic state of chromatin. Metazoan orthologs of Swr1p (Drosophila Domino; human SRCAP and p400) may have analogous functions.
[EX A]: Which protein mediates the replacement of H2A by H2A.Z in the yeast Saccharomyces cerevisiae?

[EX Q]: Les Abencerages, ou L'etendard de Grenade (English: The Abencerrages, or The Standard of Granada) is an opera in three acts by Luigi Cherubini with a French libretto by Etienne de Jouy, based on the novel Gonzalve de Cordoue by Jean-Pierre Claris de Florian.
[EX A]: Which place is Les Abencérages in?

[EX Q]: This article needs an improved plot summary. (November 2015) The Cake Eaters is a small-town, ensemble drama that explores the lives of two interconnected families coming to terms with love in the face of loss. Living in rural America, the Kimbrough family are a conflicted bunch: Easy, the patriarch and local butcher, is grieving over the recent loss of his wife, Ceci, while hiding a secret ongoing affair for years; Beagle, his youngest son who was left to care for his ailing mother, works in the local high school cafeteria by day but has a burning passion inside that manifests itself through painting street signs; and the eldest son, Guy, has been away from the family for years while pursuing his rock star dream in the big city until the day he learns of his mother's death and that he has missed the funeral. Upon Guy's return home, relationships between the characters begin to unravel: Beagle's pent up emotions connect with Georgia Kaminski, a terminally ill teenage girl wanting to experience love before it is too late; Easy's long-time affair with Marg, Georgia's eccentric grandmother, is finally exposed to the Kimbrough children; and Guy discovers that in his absence his high school sweetheart, Stephanie, has moved on and started a family of her own. Consequently, The Kimbroughs and Kaminskis manage to establish new beginnings in facing their varied relationships.
[EX A]:
What was the name of the patriarch's wife?