2019 Year 12 IB Extended Essays

Smyd1 is another candidate factor considered to be selected: it is expressed almost exclusively to cardiac myocytes with only the skeletal muscle and jejunum being the exceptions. Research showed that target deletion of this gene interfered with the formation of the right ventricle, indicating a critical role in the process of reprogramming cells to cardiac myocytes. The last candidate factor that will be selected is Mefc2, which is a common transcription factor in a number of other tissue types, resulting in a relatively low specificity to cardiomyocytes, however, it is also involved heavily in the differentiation of muscle and cardiac cells, indicating that it may contribute to the muscular and contractile properties of cardiomyocytes.

5 Conclusion

After critical evaluation considering the specificity and the functions of the transcription factors, three candidate factors (Gata4, Smyd1, Mefc2) were selected to be the final factors to add to the starting cell. The results from this investigation almost correlates with the study completed by Ieda et all in 2010, who discovered that a combination of Gata4, Mefc2c and Tbx5 ‘reprogrammed fibroblasts into functional cardiomyocytes’ (Ieda, et al., 2010). The methods completed to obtain these factors vary between the two experiments, however, the two groups of researchers both found that Gata3 and Mefc2c are two very efficient transcription factors. Researchers for this investigation picked Smyd1 over Tbx5 as the last transcription factor due to its exclusivity in muscle cells around the body, and that the deletion of this factor disrupted the maturation of cardiomyocytes, showing its importance in developing this cell type. Future extensions of this study would be testing whether this group of transcription factors is the most efficient combination. Similar to other studies mentioned earlier in this report, a starting cell type will need to be selected, this will most likely be postnatal cardiac or dermal fibroblasts, as it is a very common cell found in connective tissue around the body and are relatively easy to obtain. The transcription factors will then be introduced to these cells in order to reprogram them to differentiate into the target cell type. If successful, then these cells will grow to express markers exclusive to cardiac cells, a global gene profile similar to that of a normal cardiomyocyte and have the ability to contract spontaneously. The results from this study have raised the possibility to use a patient’s own cells or regenerative medical purposes, which not only does not require an additional donor, but also eliminates the possibility of a rejection reaction from the immune system.

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