Lecture 2 CSB351 Virology

2 Pages
263 Views
Unlock Document

Department
Cell and Systems Biology
Course
CSB351Y1
Professor
Mounir Abou Haidar
Semester
Fall

Description
Lecture2 Definition of Virus September-17-09 1:26 PM DefinitionofVirus { Viralparticlesformedofoneorseveralmoleculesofnucleicacids:RNAORDNA,butneverboth { Virus:icosahedralorhelicalshaped(RNAnotintheholeoftheloopbutispackedinsidethehelix { Capsidcoatistoprotectvirus:mostviruseshavecapsid-->somevirusesmayexistwithout { Somevirusesareparasiteofotherviruses:HepD(human)isparasiteofHepB-->stealscapsidprotein { Goodheart(1969): Virus,consistingofgeneticmaterialenclosedinaprotectivecoating Oneofthesimplestentitiestoreproduce Nometabolicsystem,nointrinsicmotility,cannotrespondtostimuli,donotgrowintheusualsense-->EXCEPTION:one bacteriavirus(tailpartcontracts,virusinjectsDNAintobacteria) Abilitytomaintaingeneticcontinuity,withpossibilityformutation,istheonlybasisforconsideringvirusestobeALIVE Viruses:ineversinglelivingorganism-->ubiquitous Thegenesaddedtocellbytheviruscausetheinfectedcelltoeitherproducemorevirusparticles(endresultcelldeath) orto changecharacteristicsofthecell(cancerous) HIV:retrovirus-->different:taketheirgeneticinfo(RNA),convertintoDNA,whichgoesintonucleusofthecell, integrateintochromosomeandstaythere-->viralgeneticinformationbecomesaPARTofgeneticinfoofthecell Allothertypes:dontgonearthenucleus-->gointocytoplasmofthecell,makesmillionsofcopiesoftheirown genethenvirusparticleandthenburstthroughthecell VirusintegratespieceofDNAnearoncogene(normalgenesinhumancellsinvolvedincelldivision-->mostof these,proto-oncogenes,usuallyturnedoffafterembryonicstage)-->viralDNAintegrationre-activateoncogene--> continuousunstoppablecelldivision-->cancer(i.e.Cervixcancer) Natureof Virus { Particlesformedofoneorseveralmoleculesofnucleicacids:RNAorDNAbutnotboth Several=Dividedgenome-->i.e.Influenzavirus(severalpiecesofRNA) One=singlegenome-->i.e.Polio,TMV { CAPSID:genomeusually(butn
More Less

Related notes for CSB351Y1

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit