BIOC20 Final Exam: BIOC20 Final Exam Study Guide Questions & Answers

How are genomes transported into the nucleus? (Ans- RNP (genome + NP + RNA polymerase complex) starts in the cytoplasm after being dumped from the endosome RNP will get into the nucleus with nuclear pore complexes (gateway for entry and exit sites in nuclear envelope) How do visions enter or exit the nucleus through Nuclear pore complexes? (Ans- Nuclear Localization Signals (NLS): anything that needs to enter nucleus must have this signal (to exit cell must have nuclear export signal) Nuclear transport receptor: importins or exportins recognize NLS/NES and carry the virion to or from the cell Nucleocapsid entry into the nucleus (Ans- Influenza RNPs have NLS so the cellular receptors (importing alphas) recognize and bind to it and work with importin beta. Importin beta interacts with importin alpha and the importin alpha directly binds to NLSHow is the viral genome transcribed in the nucleus? step 2 (Ans- The negative stranded RNA genome needs to be translated into a complimentary positive RNA strand first what is step 3 in the nucleus? (overview) (Ans- Viral mRNAs are transcribed the mRNA is made with a cap and a poly A tail, then is exported out of the nucleus and is translated by a cellular ribosome What is step 4 & 6? (overview) (Ans- Viral proteins are sent to the nucleus The protein is translated and separated into individual comps. (NP, PA, PB1, PB2, M1, NS2) These proteins are imported back into the nucleus (NLS) after being made in the. cytoplasm Step 5? (overview) (Ans- Direct genome replication and form nucleocapsids Proteins are imported back to nucleus to participate in replication or export proteins made in step 4 = replication proteins made in step 6 = exportall exported What is created using the Negative stranded RNA genome in step 5? (Ans- start w neg strand RNA genome to make mRNA transcript and to produce an anti-genome (positive strand) which can now be used as a template to create a negative strand what is step 7? (overview) (Ans- Nucleocapsids are transported to the cytoplasm The newly formed RNP needs to get to the plasma membrane and join enveloped proteins which are waiting for RNPs to arrive to they can form an envelope around M1 and NS2 play a role in export Which step involves formation of mRNA and which step involves generation of plus strand RNA (Ans- Step 2: transcribed to mRNA to create proteins Step 5: full-length minus-strand genomes to generate full-length plusstrand RNA for genome replication