Question

5. What are HeLa cells? Why are HeLa cells appropriate for this experiment? Include references to information sources used to research HeLa cells.
6. Research the function of the protein called p53. What does this function do? Explain how it can affect cell cycle control. Include references to information sources used.

7. What is the Philadelphia chromosome? How is this chromosome related to cancer? Identify how this chromosome appears physically different in a karyotype than it appears in a normal karyotype. Include references to information sources used.

Answer 1

Explanation:

5.HeLa cells (also known as "HeLa cells" or simply "Hela") are a particular type of cell culture cell, used in scientific research. It is the oldest and most frequently used human cell lineage.The HeLa cells turned out to be perfect for the polio vaccine, and that experiment and the vaccine saved millions of people.

 To develop it it was necessary for the virus to grow in the laboratory and for that human cells were required.

6. This protein is found in the nucleus of cells and plays an important role in the multiplication and destruction of cells. ... The p53 gene is a type of tumor suppressor gene.

Cell cycle arrest:

P53-mediated cell cycle arrest at the G1 / S checkpoint, when DNA damage is recognized, to prevent replication. It can be considered the main response when DNA damage occurs. The cell cycle arrest in the G1 / S transition is due to p53-dependent transcription of the CDKs inhibitor or also (CDC), cyclin-dependent kinase] called CDKN1A / p21. p21 inhibits CDK-cyclin complexes and prevents phosphorylation of pRb, so that transcription factor E2F remains inactive, and cell progression to the S phase (DNA synthesis) is prevented. This "pause" in the progression of the cell cycle gives time to repair DNA damage.

7.The Philadelphia syndrome or chromosome is an abnormality found on chromosome 22 of the body, and was discovered in 1960 by Philadelphia scientists Peter Nowell and David Hungerford; Both scientists worked in two different laboratories, but both were in the city of Philadelphia, and that is why this syndrome is named after the city in which they both discovered it.

This anomaly is linked to cancer because when presenting this anomaly of chromosomes 9 and 22, there seems to be a relationship with chronic myeloid leukemia. The truth is that, according to numerous studies carried out on patients with chronic myeloid leukemia, 90 percent of patients with this disease presented the anomaly of the Philadelphia syndrome.

The Philadelphia chromosome genetic defect consists of a phenomenon known as translocation, that is, a chromosomal break occurs in two specific regions of chromosome 9 and 22 (translocation 9-22), exchanging their positions. Specifically, the breakpoint occurs in the ABL gene (Abelson) on chromosome 9 (region q34) and in the BCR gene (Breakpoint Cluster Region, ) on chromosome 22 (region q11), giving rise to an altered chromosome 9 and a chromosome 22 also altered (Philadelphia Chromosome), but characterized by the fusion of these two genes (BCR-ABL), which encode a chimeric protein. The ABL gene takes its name from "Abelson," the name of a virus that causes leukemia, a precursor to a protein similar to that produced by this gene.

References

Zheng, Xiaomin; Güller, Saskia; Beissert, Tim; Puccetti, Elena; Ruthardt, Martin (November 7, 2006). "BCR and its mutants, the reciprocal t (9; 22) -associated ABL / BCR fusion proteins, differentially regulate the cytoskeleton and cell motility". BMC Cancer 6 (1): 262. ISSN 1471-2407. PMC PMC1637115 | pmc = incorrect (help). PMID 17090304. doi: 10.1186 / 1471-2407-6-262.