MICB 202 Lecture Notes - Lecture 11: Rna-Dependent Rna Polymerase, Viral Envelope, Rna Virus
Document Summary
Orthomyxoviruses: enveloped, rna genome, pleomorphic (many shapes, ortho = standard, myxo = mucous. Influenza a broad host range (humans, other mammals, birds) Many countries have influenza surveillance programs take samples from patients suspected of having the flu. Geographic location reflects where the virus was first isolated (may not be the region of origin, may never be known) Virus type/geographic origin/strain number/year of isolation/virus subtype. Influenza structure ( ) sense rna virus: enveloped derived from the plasma membrane of cell previously infected, pleomorphic (many shapes) does(cid:374)"t (cid:396)eall(cid:455) ha(cid:448)e a t(cid:396)ue (cid:272)apsid, proteins embedded in the envelope: Matrix protein allows h+ to enter (important for uncoating) Matrix protein 2: integral membrane protein ion channel. Each segment of the influenza genome is organized as a rnp. The rna is coated with the np protein and packaged with its own rdrp complex. Virus receptor (host): sialic acid (sa) found on membrane glycoproteins. Many mammals and birds have slightly different versions of sa.