instruction:
Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.
question:
Context: Mary Ball was born in 1812, the second daughter of Bob Stawell Ball and his wife Mary nee Green. 
 Question: Who was the male parent of Mary Ball?
answer:
bob stawell ball


question:
Context: Change in gene expression associated with pancreatic cancer could be attributed to the variation in histone posttranslational modifications leading to subsequent remodeling of the chromatin template during transcription. However, the interconnected network of molecules involved in regulating such processes remains elusive. hPaf1/PD2, a subunit of the human PAF-complex, involved in the regulation of transcriptional elongation has oncogenic potential. Our study explores the possibility that regulation of histone methylation by hPaf1 can contribute towards alteration in gene expression by nucleosomal rearrangement. Here, we show that knockdown of hPaf1/PD2 leads to decreased di- and tri-methylation at histone H3 lysine 4 residues in pancreatic cancer cells. Interestingly, hPaf1/PD2 colocalizes with MLL1 (Mixed Lineage Leukemia 1), a histone methyltransferase that methylates H3K4 residues. Also, a reduction in hPaf1 level resulted in reduced MLL1 expression and a corresponding decrease in the level of CHD1 (Chromohelicase DNA-binding protein 1), an ATPase dependent chromatin remodeling enzyme that specifically binds to H3K4 di and trimethyl marks. hPaf1/PD2 was also found to interact and colocalize with CHD1 in both cytoplasmic and nuclear extracts of pancreatic cancer cells. Further, reduced level of CHD1 localization in the nucleus in hPaf1/PD2 Knockdown cells could be rescued by ectopic expression of hPaf1/PD2. Micrococcal nuclease digestion showed an altered chromatin structure in hPaf1/PD2-KD cells. Overall, our results suggest that hPaf1/PD2 in association with MLL1 regulates methylation of H3K4 residues, as well as interacts and regulates nuclear shuttling of chromatin remodeling protein CHD1, facilitating its function in pancreatic cancer cells. 
 Question: Which is the histone residue methylated by MLL1?
answer:
h3k4


question:
Context: Patients with splenomegaly and abnormally high leukocyte counts were first recognized in France, Germany, and Scotland in the 1840s. The only well-documented therapy in the 19th century was use of arsenic in one or other form, which did undoubtedly reduce the leukocyte count but probably did little or nothing to prolong life. These early cases were probably examples of chronic myeloid leukemia (CML) (then called chronic granulocytic leukemia). In the 20th century important steps in unraveling the pathogenesis of CML were the discovery of the Philadelphia chromosome in 1960, and of the (9;22) translocation in 1973. There followed definition of the breakpoint cluster region on chromosome 22 in 1984 and the demonstration of the BCR-ABL transcript in CML in 1985. In the first half of the 20th century patients were treated predominantly with radiotherapy, and later on with busulfan, hydroxycarbamide, or interferon-alfa (IFN-). From 1980 onwards allogeneic stem cell transplantation (SCT) became the treatment of choice for eligible patients. The era of tyrosine kinase inhibitors (TKI) began in 1998 and today the use of the original TKI, imatinib, has replaced SCT as initial therapy for patients who present with CML in chronic phase. 
 Question: What tyrosine kinase, involved in a Philadelphia- chromosome positive chronic myelogenous leukemia, is the target of Imatinib (Gleevec)?
answer:

bcr-abl