Tumor viruses can infect cells through either a lytic or latent life cycle. In the latent cycle, the virus genome integrates into the host cell DNA and causes cellular transformation by interfering with normal cell growth control mechanisms. This transformation allows infected cells to proliferate unchecked and form tumors. There are two major classes of tumor viruses - DNA and RNA viruses. DNA tumor viruses like hepatitis B virus and human papillomavirus can contribute to cancers like hepatocellular carcinoma and cervical cancer. RNA tumor viruses are retroviruses that carry the enzyme reverse transcriptase and integrate their RNA genome into host cell DNA, possibly inserting oncogenes that drive transformation.
Viruses and Cancer: Introduction to OncovirusesAparna Dubey
The presentation describes about Oncoviruses or the cancer causing viruses with emphasis on HPV ( Human papillomavirus ) responsible for Cervical Cancer.
Viruses and Cancer: Introduction to OncovirusesAparna Dubey
The presentation describes about Oncoviruses or the cancer causing viruses with emphasis on HPV ( Human papillomavirus ) responsible for Cervical Cancer.
here i discussed some human oncogenic viruses , their epidemeology, life cycle, treatment, prevention and control. . oncogenic viruses are cancer causing viruses.
Basis of viral oncogenesis and the most common viruses causing cancer and their mechanism of causing cancer. Helpful for undergraduate and postgraduate teaching.
Slideshow is from the University of Michigan Medical
School's M1 Infectious Disease / Microbiology sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1IDM
An oncovirus is a virus that can cause cancer. This term originated from studies of acutely transforming retroviruses in the 1950–60s, often called oncornaviruses to denote their RNA virus origin. It now refers to any virus with a DNA or RNA genome causing cancer and is synonymous with "tumor virus" or "cancer virus".
here i discussed some human oncogenic viruses , their epidemeology, life cycle, treatment, prevention and control. . oncogenic viruses are cancer causing viruses.
Basis of viral oncogenesis and the most common viruses causing cancer and their mechanism of causing cancer. Helpful for undergraduate and postgraduate teaching.
Slideshow is from the University of Michigan Medical
School's M1 Infectious Disease / Microbiology sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1IDM
An oncovirus is a virus that can cause cancer. This term originated from studies of acutely transforming retroviruses in the 1950–60s, often called oncornaviruses to denote their RNA virus origin. It now refers to any virus with a DNA or RNA genome causing cancer and is synonymous with "tumor virus" or "cancer virus".
oncogenic viruses by dr rahul acharya.pptxrahulacharya52
Epstein–Barr virus (EBV), hepatitis B virus (HBV), human T-lymphotropic virus 1 (HTLV-1), human papillomaviruses (HPVs), hepatitis C virus (HCV), Kaposi sarcoma-associated herpesvirus (KSHV; also known as human herpesvirus 8 (HHV-8)) and Merkel cell polyomavirus
Double branded DNA viruses (select only one answer) all insert their.pdfarchgeetsenterprises
Double branded DNA viruses (select only one answer) all insert their genome into the host\'s
genome to be translated and transcribed likely have a slower rates of mutation than RNA viruses
never cause diseases are more common than RNA viruses are responsible for 45% of the
human genome because of their insertions
Solution
The double-stranded DNA viruses are unique pathogens which require a DNA intermediate for
replication of new viral particles using reverse transcriptase enzyme. These viruses are
particularly shown to be highly active pathogens for human and higher vertebrate infections from
primitive times. They are less common than RNA viruses. However, like other RNA/DNA
viruses, they too possess high mutation rates owing to faulty replication and lack of proof-
reading by polymeraes. Importantly, as a mode of infection, all of these viruses do insert their
genome or a part of it in the host cell\'s genome to promotes its transcription and translation. This
is why double-stranded DNA viruses are difficult to eradicate from human/vertebrate hosts
because they very easily modulate their molecular functions according to the host machinery.
Some examples of diseases caused by such viruses are small pox, herpes infection etc.
Thus, the above explanations states that choice 1 is most correct..
introduction
What is virus
What is virus resistance plant
History
Gene use for develop virus resistance plant
Coat protein gene
cDNA of satellite RNA
Defective viral genome
Antisense RNA approach and
Ribozyme – mediated protection
conclusion
References
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Safalta Digital marketing institute in Noida, provide complete applications that encompass a huge range of virtual advertising and marketing additives, which includes search engine optimization, virtual communication advertising, pay-per-click on marketing, content material advertising, internet analytics, and greater. These university courses are designed for students who possess a comprehensive understanding of virtual marketing strategies and attributes.Safalta Digital Marketing Institute in Noida is a first choice for young individuals or students who are looking to start their careers in the field of digital advertising. The institute gives specialized courses designed and certification.
for beginners, providing thorough training in areas such as SEO, digital communication marketing, and PPC training in Noida. After finishing the program, students receive the certifications recognised by top different universitie, setting a strong foundation for a successful career in digital marketing.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...
Dibakar ppt
1. Tumor Viruses and Cell Transformation- Role in Cancer Initiation and Prevention
2. Tumor Viruses Lytic Life Cycle For most viruses: Genome viral proteins Replication Lysis Progeny virions
3. Tumor Viruses Latent Life Cycle Virus Cell Integration (usually) Transformation Virus-specific proteins expressed - No mature virus Changes in the properties of host cell - TRANSFORMATION
4. Tumor Viruses Transformation: Loss of growth control Ability to form tumors - viral genes interfere with control of cell replication
5. TRANSFORMATION Both DNA and RNA tumor viruses can transform cells Integration occurs (usually) Similar mechanisms VIRAL TRANSFORMATION The changes in the biological functions of a cell that result from REGULATION of the cell’s metabolism by viral genes and that confer on the infected cell certain properties characteristic of NEOPLASIA These changes often result from the integration of the viral genome into the host cell DNA
6.
7. Two Major Classes of Tumor Viruses DNA Tumor Viruses DNA viral genome Host RNA polymerase Viral mRNA Viral protein DNA-dependent DNA polymerase (Host or viral)
8. Important: Use HOST RNA polymerase to make its genome An enzyme that normally makes mRNA IMPORTANT RNA Tumor Viruses Viral RNA genome Reverse transcriptase (Virus-encoded) Viral DNA genome (integrated) DNA-dependent RNA polymerase ( Host RNA pol II) Viral genomic RNA Splicing (Host splicing enzymes) messenger RNA viral protein Virus
9. DNA Tumor Viruses DNA genome mRNA protein virus Host RNA polymerase II Host enzymes OR TRANSFORMATION In transformation usually only EARLY functions are expressed
10. DNA Tumor Viruses In Human Cancer Epidermodysplasia verruciformis Papilloma virus
11. DNA Tumor Viruses In Human Cancer ONCOGENE A gene that codes for a protein that potentially can transform a normal cell into a malignant cell An oncogene may be transmitted by a virus in which case it is known as a VIRAL ONCOGENE v-onc
12.
13. DNA Tumor Viruses In Human Cancer Host enzyme Viral enzyme Hepatitis B Virus DNA genome RNA polymerase II RNA Provirus Reverse transcriptase DNA genome
14. DNA Tumor Viruses In Human Cancer Hepatitis B continued Epidemiology: Strong correlation between HBV and hepatocellular carcinoma China: 500,000 - 1 million new cases of hepatocellular carcinoma per year Taiwan: Relative risk of getting HCC is 217 x risk of non-carriers
15. RNA Tumor Viruses RNA Genome - Retroviruses RNA-dependent DNA Polymerase encoded by virus REVERSE TRANSCRIPTASE RNA genome Reverse transcriptase DNA genome Integrase Integrates Host RNA polymerase II RNA genome host virus virus
22. RNA Tumor Viruses Retrovirus Life Cycle Endocytosis Fusion of membranes Release of nucleocapsid to cytoplasm Nucleus
23.
24. RNA Tumor Viruses Drawback to this lifestyle Genomic RNA DNA Genomic RNA Pol II is a host enzyme that, in the uninfected cell, makes mRNA When making mRNA, pol II does not copy entire gene to RNA Host RNA pol II Reverse transcriptase
25. primer Viral genomicRNA Reverse transcriptase dsDNA Result: New copy of viral RNA is shorter - lacks control sequences Problem of using RNA pol II to copy a gene RT promotor RNA synthesis initiation site RNA pol II RNA synthesis termination site
26. RNA Tumor Viruses Clue: Difference in the two forms RNA R U5 GAG POL ENV U3 R LTR Repeat region Repeat region DNA U3 R U5 GAG POL ENV U3 R U5
27. Feline Sarcoma Virus (FSV) R U5 dGAG FMS dENV U3 R Avian Myelocytoma Virus (MC29) R U5 dGAG MYC dENV U3 R Avian Myeloblastosis Virus R U5 GAG POL MYB U3 R Some retroviruses have an oncogene instead of their regular genes
30. RNA Tumor Viruses The discovery of the acutely transforming retroviruses that contain v-oncs explains how cancers may arise as a result of infection These viruses cause rapid cancer in animals in the laboratory
31. RNA Tumor Viruses In contrast: Chronically transforming retroviruses cause tumors inefficiently after prolonged period of time No oncogene! – How does it cause a tumor? R U5 GAG POL ENV U3 R Avian Leukosis Virus (causes lymphomas)
32.
33. Cancers often result from gene translocations Burkitt’s Lymphoma 8:14 translocation Break in chromosome 14 at q32 Acute myelocytic leukemia myc
34.
Editor's Notes
In previous lectures we have looked at the replication of viruses. How the genome gives rise to viral proteins
Some viruses may lay latent in the cell for a very long time (and then may possibly lyse the cell). In this case only early functions of these viruses may be expressed. This results in virus proteins being expressed but no mature virus particles. The expression of these early virus proteins may nevertheless alter the properties of the infected cell. THE CELL IS SAID TO BE VIRALLY TRANSFORMED.
Viral genes interfere with cell replication control mechanism. NOTE: The early functions of DNA viruses do not make structural proteins but control cellular and viral genome replication.
Permissive cells: Replication, lysis and death Non-permissive cells: transformation. Usually DNA is integrated. Early functions only are expressed. Control information, rather than structural proteins
Most people have antibodies against EBV Why some populations get mononucleosis while others get tumors in not known Causes lymphoma in marmosets
Reverse transcriptase is not a capacity possessed by normal eucaryotic cells Many features are unique to retroviruses Very unusual mode of replication which gives them the potential to transform the cell But when it comes to how these viruses cause neoplasia, they may be very similar to DNA viruses Rous sarcoma virus in chickens was the first retrovirus to be discovered. It causes an aggressive acute cancer in chickens
Even though the virus RNA is same sense (positive) as mRNA, it cannot be translated directly as it is encapsulated by proteins. Thus it must be copied via a negative sense nucleic cid (in this case via DNA). Virus contains about 10 copies of reverse transcriptase. NOTE: Both copied of single strand RNA are identical
When integrated viral genes may or may not be expressed If expressed, all are expressed at least in the simpler retroviruses (why we shall see later) Whether host polymerase makes mRNA or genomic RNA depends on the processing by the host cell splicing enzymes Nucleocapsid assembly is in the cytoplasm and reverse transcriptase is packed into the virus Virus buds through the plasma membrane where it picks up the viral glycoprotein Maturation occurs in the budded virus
To make an RNA using RNA pol II, sequences other than those to be transcribed are required. Thus the DNA “gene” is bigger than the mRNA that is transcribed from it. These extra sequences can be upstream or downstream from the transcribed portion. They include: promotors, enhancers, termination sequences. Thus these “control” sequences will be lost on reconversion of the viral genome to RNA. These sequences are necessary for transcription of mRNA but not the translation of mRNA
These viruses cannot make all of their proteins and so need a co-infecting “helper” virus Viral oncogenes have three letter names e.g. src, myb
Retroviruses that cause acute transformation (rapid onset of neoplasia) such as RSV have an extra gene. These neoplasms are usually only seen in laboratory situations. The viral oncogene causes cells to be released from their normal growth controls. These extensively characterized genes are NOT UNIQUE to retroviruses. cDNA probes against viral oncogenes show similar homologues in NORMAL eucaryotic cells . These cellular homologues are not identical to the viral oncogene and it seems that the virus has picked up a cellular gene during its evolution. The discovery of normal homologues of viral oncogenes was a great step forward in the cell biology of cancer. The cellular proto-oncogenes are a family of genes that may underlie much of carcinogenesis. BUT a cellular oncogene does not cause cancer normally. Why does it do so in a virus?
Remember: A virus has only one end: to reproduce. This means that the genome and proteins have to be made in large numbers. So many more copies of the v-onc mRNA are made than the c-onc RNA. This over expression may be the basis of the transformation that is seen
Could the break and exchange of parts of chromosomes bring the c-onc under the control of a very active cell promotor? In Burkitt’s lymphoma there is a 8:14 translocation. Myc is at the break site on chromosome 8. What does it come next to on chromosome 14?