Please answer both questions correctly! Thank you! :) 1. Is SV40 mRNA transcript
ID: 85274 • Letter: P
Question
Please answer both questions correctly! Thank you! :)1. Is SV40 mRNA transcription and DNA replication similar to its host cell?
2. Explain the HPV model for cell transformation and include both virus and cell factors.
Please answer both questions correctly! Thank you! :) Please answer both questions correctly! Thank you! :)
1. Is SV40 mRNA transcription and DNA replication similar to its host cell?
2. Explain the HPV model for cell transformation and include both virus and cell factors.
Please answer both questions correctly! Thank you! :) Please answer both questions correctly! Thank you! :)
2. Explain the HPV model for cell transformation and include both virus and cell factors.
Please answer both questions correctly! Thank you! :)
Explanation / Answer
1. Simion Virus 40 or Simian vacuolating virus 40 is grouped under polyomavirus and they are known to be found in monkeys and humans.
SV40 genome has extensively studied and thus we know its transcription nd replication mechanisms. Its genome is the best understood eukaryotic DNA replication process. It has a geome that conatins circular duplex DNA organized in a single replicon.
The striking feature of it is that it has similarity with host genome replication pattern, its small genome gets associated with host histones in nucleosomes, and also important part is it is dpedendent on host cell milieu for replication factors and precursors which has helps in its adaptations. The negative supercoiled topology in its genome endows chromatin that can mimic and start like an initiation of DNA replication or transcription.
2. HPV or Human Papillomavirus induced transformation or oncogenesis is related to the capacity of thevirus and its particles to cause potential harm to the host. This virus is a small nonenveloped viruses with 55-nm-diameter icosahedral capsids, its genome size is approximately 8,000 bp. It is widely distributed in animal kingdom the specific infection happens to be in squamous epithelia, thus warts generation happens. From the identified 200 species of them they are classified into mucosal and cutaneous HPVs. Most HPVs can cause and form malignant progression through infection, in this portion we will look into some of its viral factors and cell factors.
From its 16 double-stranded circular DNA genome we can see that Early and Late genes arises to infect and transform a host cell environment. It has got an early promoter known as P97 . HPV E6/E7 genes are consistently expressed, while other genes are not transcribed or deleted after integration into host cell. Then the production of HPV RNA species occurs. From the HPV transcripts points of view E7 gene and use cellular splicing and polyadenylation signals in case of cervical cancer cells. Another two protein known as E1 and E2 helps in viral genome replication. E2 is a viral genome replication and possess the capacity for transcriptional activators. E1 is a viral DNA helicase.
The host cell is infected in epithelium cell layers, initially infect basal epithelial cells. The viral DNA as a low copy number in the nuclei of infected host cells, when they are preparing to differentiate for infection to start. A high copy number is seen in terminally differentiated cells. This nonlytic viruses shed into the environment as a cargo within epithelial squamae. Another interesting thing is HPV E4 protein associates with keratin intermediate filaments, which is helpful for its mechanical stability of the keratin network and may facilitate the release of viral particles