Question e.Prepare a written description of the data in Figure 1. This should be a summary block of text that includes reference to the relevant data figure panels, their interpretation and any conclusions that can be drawn as to the role of the 3 and 5 UTRs. (10 marks) as this description answers below for question E chech editing, please?: Part e) The study described in the text aimed to examine the effect of the 3' and 5' UTRs of the BACE1 mRNA on its translation into protein. To do this, different expression constructs were introduced into HEK 293 cells, including the BACE1 Open Reading Frame (ORF) and variants with additional 5' UTR or 3' UTR flanking sequences. The level of BACE1 protein was measured in the transfected cells using Western blot analysis and an anti-BACE1 antibody. Additionally, the influence of the 5' UTR on expression was evaluated using a luciferase reporter gene, where the 5' UTR of BACE1 was fused to the luciferase ORF (Miller et al., 2021). Transiently transfected HEK 293 cells expressing various forms of BACE1 are shown in Western blot (A) in Figure 1 below. The data show that the BACE1 protein is expressed less when the 5' UTR flanking region is included in comparison to when the BACE1 ORF is used alone. Western blotting study of BACE1 ORF and BACE1 variant with 5' UTR flanking sequence transfected H4 and COS7 cells is depicted in Figure 1 (B). Reductions in BACE1 expression were also seen in H4 and COS7 cells, suggesting that the phenomenon is not exclusive to HEK 293 cells. HEK 293 cells were transfected with luciferase encoding the 5' UTR of BACE1 or with luciferase as a control, and the results of the luciferase activity measurements are shown in Figure 1 (C). According to the findings, the expression of the chimeric luciferase construct is significantly influenced by the 5' UTR of BACE1, such that its activity is decreased in comparison to the control. How mach the diiffrencecs between two results Based on the data shown in Figure 1, it appears that the 5' UTR of the BACE1 mRNA significantly affects the expression of BACE1 protein, decreasing it in comparison to the ORF alone. The 5' untranslated region (UTR) has a substantial effect on chimeric luciferase production. These findings support a critical role for the 5' UTR of the BACE1 mRNA in controlling the level of BACE1 protein production. In cell biology experiments, it is common to use different cultured cell lines, to ensure that the observed results are real. In this study, three types have been used called HEK293, H4 and COS7. For the purposes of this TMA, the specific type of cells is irrelevant. Transfection is the technique by which DNA is introduced into cultured cells in the laboratory. When DNA is introduced into such cells, expression is often monitored a short time after transfection, after the cellular components have transcribed and translated the introduced gene. These short-term experiments are called transient transfections. In this case, .

1. Question e.Prepare a written description of the data in Figure 1. This should be a summary
block of text that includes reference to the relevant data figure panels, their interpretation
and any conclusions that can be drawn as to the role of the 3 and 5 UTRs. (10 marks)
as this description answers below for question E chech editing, please?:
Part e)
The study described in the text aimed to examine the effect of the 3' and 5' UTRs of the BACE1
mRNA on its translation into protein. To do this, different expression constructs were introduced
into HEK 293 cells, including the BACE1 Open Reading Frame (ORF) and variants with
additional 5' UTR or 3' UTR flanking sequences. The level of BACE1 protein was measured in
the transfected cells using Western blot analysis and an anti-BACE1 antibody. Additionally, the
influence of the 5' UTR on expression was evaluated using a luciferase reporter gene, where the
5' UTR of BACE1 was fused to the luciferase ORF (Miller et al., 2021).
Transiently transfected HEK 293 cells expressing various forms of BACE1 are shown in
Western blot (A) in Figure 1 below. The data show that the BACE1 protein is expressed less
when the 5' UTR flanking region is included in comparison to when the BACE1 ORF is used
alone.
Western blotting study of BACE1 ORF and BACE1 variant with 5' UTR flanking sequence
transfected H4 and COS7 cells is depicted in Figure 1 (B). Reductions in BACE1 expression
were also seen in H4 and COS7 cells, suggesting that the phenomenon is not exclusive to HEK
293 cells.
HEK 293 cells were transfected with luciferase encoding the 5' UTR of BACE1 or with
luciferase as a control, and the results of the luciferase activity measurements are shown in
Figure 1 (C). According to the findings, the expression of the chimeric luciferase construct is
significantly influenced by the 5' UTR of BACE1, such that its activity is decreased in
comparison to the control. How mach the diiffrencecs between two results
Based on the data shown in Figure 1, it appears that the 5' UTR of the BACE1 mRNA
significantly affects the expression of BACE1 protein, decreasing it in comparison to the ORF
alone. The 5' untranslated region (UTR) has a substantial effect on chimeric luciferase
production. These findings support a critical role for the 5' UTR of the BACE1 mRNA in
controlling the level of BACE1 protein production.
In cell biology experiments, it is common to use different cultured cell lines, to ensure that the
observed results are real. In this study, three types have been used called HEK293, H4 and
COS7. For the purposes of this TMA, the specific type of cells is irrelevant. Transfection is the
technique by which DNA is introduced into cultured cells in the laboratory. When DNA is
introduced into such cells, expression is often monitored a short time after transfection, after the
cellular components have transcribed and translated the introduced gene. These short-term
experiments are called transient transfections. In this case, the level of expression of the gene is
usually controlled by comparing it to a second gene that is transfected with the test gene. The

2. level of expression of this second gene might be assessed as an enzyme activity or by Western
blotting, depending upon the gene used. This serves to allow for comparisons between
experiments as it can serve as a control. For the experiments described in Figure 1, HEK293 cells
were transiently transfected with expression constructs containing the BACE1 ORF or the
BACE1 variants with additional 5' UTR or 3' UTR flanking sequences and an equal amount of
an expression vector containing GFP-encoding DNA. After suitable incubation to allow for
expression, cell lysates were prepared and analysed for BACE1 protein by immunoblotting with
anti-BACE-1, and for GFP with anti-GFP antibody with signal detection using a
chemiluminescence assay. For luciferase activity, HEK293 cells were transfected with constructs
containing either 5 UTRBACE1 sequences fused to the luciferase ORF or luciferase-encoding
DNA alone (without the UTR BACE1 sequences). An expression construct containing a gene
encoding secretory alkaline phosphatase (SEAP) was co-transfected into cells along with
luciferase containing constructs. Cell lysates were then prepared and a portion of cell lysates was
used for luciferase activity measurements and a portion for SEAP activity measurements. B C
Figure 1 (A) HEK293 cells were transiently transfected with BACE1, or BACE1 constructs
containing the 5' UTR or 3' UTR of BACE1 as shown. Equal total amounts of protein were
loaded in all tracks. (B) Reduction of BACE1 expression is not cell-type specific. H 4 and COS 7
cells were transfected with BACE1 or 5' UTR BACE1 and analysed by Western blotting (upper
panels). GFP was used as a positive control (lower panels). (C) Influence of the BACE1 5' UTR
on the expression of a chimeric luciferase (Luc) construct. HEK293 cells were transfected with
luciferase containing the 5' UTR of BACE1 or with luciferase as control. The signal for
luciferase without 5' UTR was set to 100% . Luciferase activity was corrected for secretory
alkaline phosphatase activity. Results were expressed as the mean and standard deviation of three
independent experiments made in duplicate. Note that while this question refers to data from
Western blotting experiments, you do not need to have completed El4 (Analysing gene
expression - Western blotting) in order to answer it. You only need to understand that Western
blotting is being used here to examine the relative amounts of specific proteins in cell lysates.