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

[Q]: In yeast, the macromolecular complex Set1/COMPASS is capable of methylating H3K4, a posttranslational modification associated with actively transcribed genes. There is only one Set1 in yeast; yet in mammalian cells there are multiple H3K4 methylases, including Set1A/B, forming human COMPASS complexes, and MLL1-4, forming human COMPASS-like complexes. We have shown that Wdr82, which associates with chromatin in a histone H2B ubiquitination-dependent manner, is a specific component of Set1 complexes but not that of MLL1-4 complexes. RNA interference-mediated knockdown of Wdr82 results in a reduction in the H3K4 trimethylation levels, although these cells still possess active MLL complexes. Comprehensive in vitro enzymatic studies with Set1 and MLL complexes demonstrated that the Set1 complex is a more robust H3K4 trimethylase in vitro than the MLL complexes. Given our in vivo and in vitro observations, it appears that the human Set1 complex plays a more widespread role in H3K4 trimethylation than do the MLL complexes in mammalian cells.
[A]: Which is the histone residue methylated by MLL1?


[Q]: Imatinib was the first BCR-ABL tyrosine kinase inhibitor to become clinically available. In this study, we retrospectively evaluated the long-term efficacy of low-dose imatinib (final maintenance dose <300mg per day) due to intolerance, in comparison to optimal-dose imatinib (300mg per day) in patients with Philadelphia chromosome-positive chronic myeloid leukemia in the chronic phase. The Kaplan-Meier estimates of the median time to complete cytogenetic response, major molecular response, and complete molecular response were longer for 31 patients receiving low-dose imatinib (360, 1360, and 1420days, respectively) than 74 patients receiving optimal-dose imatinib (170, 420, and 720days, respectively). However, the differences in response shrank over time and progression-free survival were comparable between the two groups. These findings suggest that long-term treatment with low-dose imatinib is an acceptable alternative for patients with intolerance to the optimal dose.
[A]: What tyrosine kinase, involved in a Philadelphia- chromosome positive chronic myelogenous leukemia, is the target of Imatinib (Gleevec)?


[Q]: Somatic mutations in the tyrosine kinase (TK) domain of the epidermal growth factor receptor (EGFR) gene are reportedly associated with sensitivity of lung cancers to gefitinib (Iressa), kinase inhibitor. In-frame deletions occur in exon 19, whereas point mutations occur frequently in codon 858 (exon 21). We found from sequencing the EGFR TK domain that 7 of 10 gefitinib-sensitive tumors had similar types of alterations; no mutations were found in eight gefitinib-refractory tumors (P = 0.004). Five of seven tumors sensitive to erlotinib (Tarceva), a related kinase inhibitor for which the clinically relevant target is undocumented, had analogous somatic mutations, as opposed to none of 10 erlotinib-refractory tumors (P = 0.003). Because most mutation-positive tumors were adenocarcinomas from patients who smoked <100 cigarettes in a lifetime ("never smokers"), we screened EGFR exons 2-28 in 15 adenocarcinomas resected from untreated never smokers. Seven tumors had TK domain mutations, in contrast to 4 of 81 non-small cell lung cancers resected from untreated former or current smokers (P = 0.0001). Immunoblotting of lysates from cells transiently transfected with various EGFR constructs demonstrated that, compared to wild-type protein, an exon 19 deletion mutant induced diminished levels of phosphotyrosine, whereas the phosphorylation at tyrosine 1092 of an exon 21 point mutant was inhibited at 10-fold lower concentrations of drug. Collectively, these data show that adenocarcinomas from never smokers comprise a distinct subset of lung cancers, frequently containing mutations within the TK domain of EGFR that are associated with gefitinib and erlotinib sensitivity.
[A]:
Mutations in which gene determine response to both erlotinib and gefitinib?