Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

[EX Q]: Context: Chlorophyll b is a major photosynthetic pigment in green plants that is synthesized by chlorophyllide a oxygenase (CAO). The regulation of chlorophyll b biosynthesis is an important determinant for the antenna size of photosystems. Chlorophyll b synthesis is partly regulated on a transcriptional level by the expression of the CAO gene. In addition, the synthesis of chlorophyll b is strictly regulated on a protein level by the stability of the CAO enzyme. CAO consists of three domains, which are sequentially named from the N terminus as the A, B and C domains. The A domain of CAO participates in the regulation of the CAO protein stability.', 'In order to clarify the physiological function of the A domain, we constructed transgenic Arabidopsis (Arabidopsis thaliana) plants which either overexpressed the complete CAO or a truncated version of CAO lacking the A domain. The transgenic plants overexpressing the A-domain-deleted CAO accumulated an excess amount of chlorophyll b during greening. The transgenic plants which lacked the A domain either died or were obviously retarded when they were exposed to continuous light immediately after etiolation. In addition, the loss of the A domain in CAO impaired another step of chlorophyll biosynthesis, namely the conversion of divinyl-protochlorophyllide a to monovinyl protochlorophyllide a under dark conditions.
Answer: The A domain of CAO regulates the level of CAO, and thus prevents the excess accumulation of chlorophyll b. This function of the A domain is especially important during the greening stage of etiolated seedlings. At this stage, the plants are vulnerable to photodamages which could be caused by excessive chlorophyll b accumulation. In addition, de-regulation of the CAO level affects monovinyl-protochlorophyllide biosynthesis in darkness by unknown mechanisms. In conclusion, the A domain of CAO is essential in the control of chlorophyll biosynthesis and in the survival of seedlings during de-etiolation especially under strong illumination.
[EX A]: Does loss of the N-terminal domain of chlorophyllide a oxygenase induce photodamage during greening of Arabidopsis seedlings?

[EX Q]: Context: We investigated in vitro whether IL-1beta and TGF-beta1 affect pancreatic cancer cell growth, adhesion to the extracellular matrix and Matrigel invasion.', 'Adhesion to fibronectin, laminin and type I collagen, and Matrigel invasion after stimulation with saline, IL-1beta and TGF-beta1 were evaluated using three primary and three metastatic pancreatic cancer cell lines.', 'Extracellular matrix adhesion of control cells varied independently of the metastatic characteristics of the studied cell lines, whereas Matrigel invasion of control cells was partly correlated with the in vivo metastatic potential. IL-1beta did not influence extracellular matrix adhesion, whereas it significantly enhanced the invasiveness of three of the six cell lines. TGF-beta1 affected the adhesion of one cell line, and exerted contrasting effects on Matrigel invasion of different cell lines.
Answer: IL-1beta enhances the invasive capacity of pancreatic cancer cells, whereas TGF-beta1 has paradoxical effects on pancreatic cancer cells; this makes it difficult to interfere with TGF-beta1 signaling in pancreatic cancer treatment.
[EX A]: Is pancreatic cancer cells invasiveness mainly affected by interleukin-1beta not by transforming growth factor-beta1?

[EX Q]: Context: In order to determine the synergistic effects of human placental mesenchymal stem cells (PMSCs) on hematopoiesis in vivo, we compared the intrabone marrow injection (IBMI) with the conventional intravenous injection (IVI).', 'C57BL/6 recipient mice conditioned with lethal doses of irradiation were transplanted with bone marrow mononuclear cells (MNCs) and bone marrow-derived mesenchymal stem cells (BMSCs) from BALB/c mice by IBMI or IVI. NOD/SCID recipient mice conditioned with sublethal doses of irradiation were transplanted with human umbilical cord blood MNCs (UCB-MNCs) and PMSCs by IBMI or IVI.', 'The number of hematopoietic cells was significantly higher in mice transplanted with BMSCs by IBMI than in those transplanted by IVI in a murine transplantation model (BALB/c→C57BL/6). Moreover, the percentage of human hematopoietic cells in the tibiae of the NOD/SCID mice that were transplanted with PMSCs plus UCB-MNCs was higher than that in mice transplanted with UCB-MNCs alone. In addition, in mice that were transplanted with PMSCs, PMSCs injected by IBMI were more efficient than those injected by IVI.
Answer: Our results not only elucidated the role of PMSCs in promoting hematopoiesis, but also revealed the therapeutic potential of the combination of PMSCs and IBMI in transplantation.
[EX A]:
Does intrabone marrow injection enhance placental mesenchymal stem cellmediated support of hematopoiesis in mice?