Tumor Virus and Retrovirus
Where do oncogenes come from?
*MISTAKE IS MADE IN SPLICING; PROTO-ONCOGENE CAPTURED 1. oncogene gene sequence becomes complex or long 2. acute transforming virus loses its place in the sequence and loses RNA 3. It become defective acute transforming virus 4. it requires co infection virus to cause cancer
factors of AIDs
1. present in filtered blood products 2. delayed onset between exposure and development of disease 3. immunodeficiency occurs with other animal retroviruses 4. destructs t helper lymphocytes (HTLV-1 & HTLV-2 are t cell tropic)
AIDS aka
Acquired Immune Deficiency Syndrome
Proto-oncogenes wait until their activated by ____ ____ or _____ ____.
DNA mutation; retrovirus infection
an example of Blow
HIV destroying T-cells
HIV (potential antigens)
Nucleocapsid (NC) proteins Capsid (CA) proteins Matrix proteins Glycoproteins
Sarcoma is caused by
Rous sarcoma virus
Define integrase
The sticky ends of acute transforming virus which allows it to attach to host DNA
How is retroviridae different from other RNA viruses?
because they have reverse transcriptase (converts RNA to DNA)
what makes up the capsid shell
capsid proteins
env
codes for envelope proteins gp 120 and gp 41 proteins
gag (group antigens)
codes for proteins inside the cell envelope (NC, CA, MA), hence code for the major structural proteins
pol
codes for vital protease, integrase and reverse transcriptase enzyme. The protease encoded by this gene plays a role in maturation of the gag encoded proteins.
HIV genome sequences
gag, pol, env
gp 120 and gp 41 proteins come together to form the
gp 160 protein
Human T-cell Leukemia virus variant II (HTLV-II) was isolated from patients with what disease
hairy cell leukemia
The function of the gp 160 protein is to
help the virus bind to the T-cells
matrix protein function
holds the glycoprotein spikes that transverse the lipid bilayer membrane (envelope)
Human T-cell Leukemia virus (HTLV-1) was isolated from patients with what disease & is aka
human T-cell leukemia and tropic spastic paraparesis
what is p24 used for
it is measured in the serum to detect early HIV infection
Retroviridae
large group of RNA viruses that infect humans and animals
Most retroviruses cause what two diseases?
leukemia or sarcoma
leukemia is caused by
leukemia sarcoma viruses
proteins under the envelope
matrix proteins
what is the shape of HIV
nucleocapsid
what is located at the virion core of HIV
nucleocapsid and 3 retrovirus enzymes
Some viruses may carry ______ in their ____.
oncogenes; genome
what is the major capsid protein
p24
what are the 3 retrovirus enzymes and where are they located
protease, reverse transcriptase, integrase; HIV virion core
inactive oncogenes are aka
proto-oncogenes
LTR
recognize by integrase to help it integrate into the genome and act as a promoter
surface glycoproteins
referred to as gp 120 and gp 41
The three concepts to remember about the retroviridae virus
retro, grow, blow
What virus has the ability to convert RNA to DNA?
retroviridae
Retro
retroviridae is different from any other RNA viruses because it has reverse transcriptase (RNA to DNA)
Grow
retrovirus can cause cancer in cells that they infect
The conversion of RNA to DNA is aka
reverse transcriptase
Blow
some retroviruses are cytotoxic to certain cell causing them to explode
Rous sarcoma virus has which oncogene?
src
what surrounds the RNA core (HIV core) and what shape is it
the capsid shell; icosahedral
newly identified HIV genome regulatory genes
vif, vpr, nef, vpu
HIV genome (regulatory genes)
vif, vpr, nef, vpu, tat, rev
defective acute transforming viruses
when viruses have lost their own RNA which is critical for replication
