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

Input: Consider Input: SET domain methyltransferases deposit methyl marks on specific histone tail lysine residues and play a major role in epigenetic regulation of gene transcription. We solved the structures of the catalytic domains of GLP, G9a, Suv39H2 and PRDM2, four of the eight known human H3K9 methyltransferases in their apo conformation or in complex with the methyl donating cofactor, and peptide substrates. We analyzed the structural determinants for methylation state specificity, and designed a G9a mutant able to tri-methylate H3K9. We show that the I-SET domain acts as a rigid docking platform, while induced-fit of the Post-SET domain is necessary to achieve a catalytically competent conformation. We also propose a model where long-range electrostatics bring enzyme and histone substrate together, while the presence of an arginine upstream of the target lysine is critical for binding and specificity. This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1.

Output: What is the characteristic domain of histone methyltransferases?

Input: Consider Input: Protein kinases (PKs) and lipid kinases (LKs) are good choices for targets of signal transduction therapy as these enzymes are involved in signaling pathways, and are often related to the pathogenesis of lymphoid malignancies. The attractiveness of PKs and LKs as drug able targets is enhanced by the fact that they are enzymes whose biological activity can be turned off by drugs that block their catalytic site. In the last few years small molecular kinase inhibitors (KIs) have been synthesized and become available for preclinical studies and clinical trials. The first KI, introduced into clinical practice in 1998, was imatinib mesylate, which became the first choice drug in chronic myeloid leukemia. More recently, several KIs have been developed to target the proximal B-cell receptor (BCR) signaling pathway including spleen tyrosine kinase inhibitor (Fostamatinib) and Bruton's tyrosine kinase inhibitors (Ibrutinib, AVL-263). These agents are currently evaluated in early clinical trials in chronic lymphocytic leukemia (CLL) and other diseases. Cyclin-dependent kinase (Cdk) inhibitors, flavopiridol (alvocidib), BMS-387032 (SNS-032), sunitinib and sorafenib are currently under evaluation in clinical trials for relapsed/refractory CLL. Multi-tyrosine kinase inhibitors including vandetanib (ZD6474) bosutinib (SKI-606), TKI258 (CHIR-258), pazopanib (GW786034) and axitinib (AG013736) have been also developed for the treatment of lymphoid malignancies. Phosphatidylinositol 3-kinases (PI3K ) are a family of lipid kinases that mediate signals from cell surface receptors. CAL-101 (GS-1101) is an oral PI3K-specific inhibitor which has shown preclinical and clinical activity against CLL. This article summarizes recent achievements in the mechanism of action, pharmacological properties and clinical activity and toxicity of PK and LK inhibitors in CLL.

Output: What is the name of Bruton's tyrosine kinase inhibitor that can be used for treatment of chronic lymphocytic leukemia?

Input: Consider Input: As of the census of 2000, there were 325,957 people, 149,937 households, and 94,460 families residing in the county. The population density was 570 people per square mile (220/km2). There were 182,467 housing units at an average density of 319 per square mile (123/km2). The racial makeup of the county was 92.65% Race (United States Census), 4.18% Race (United States Census) or Race (United States Census), 0.22% Race (United States Census), 0.77% Race (United States Census), 0.03% Race (United States Census), 1.14% from Race (United States Census), and 1.02% from two or more races. 4.34% of the population were Race (United States Census) or Race (United States Census) of any race. 89.7% spoke only English language at home; 4.4% spoke Spanish language, 1.3% German language, and 1.0% French language at home.
Output: Which group is smaller for the county according to the census: people or households?