Self assessment Lecture 38 Translation 1 Please compare and contrast translation in prokaryotes and eukaryotes a Similarities both use ribosomes the universal code and tRNAs b Differences i Prokaryotes 1 Transcription occurs at the same time same place as transcription 2 The initiator methionine is formylated 3 Message is generally polycistronic having multiple coding regions 4 Initiation relies on recognition of purine rich Shine Delgarno Sequence by 16s rRNA ii Eukaryotes 1 Circular mRNA is recognized by both the 5 cap and 3 poly A tail 2 Ribosome binds at the cap and scans for the first AUG codon 2 In translation the template is read 3 5 5 3 and the amino acids are added N terminus to C terminus C terminus to N terminus 3 What specifies which amino acid is added to the peptide chain Is it the anticodon or the amino acid which is bound to the tRNA that is recognized as correct 4 Please write the two reactions that result in the charging of a tRNA to form an aminoacyl tRNA a Amino acid ATP D Aminoacyl AMP PPi b Aminoacyl AMP tRNA D Amino Acyl tRNA AMP 5 The reactions in Q4 are catalyzed by aminoacyl tRNA synthetase 6 Initiation factors IF1 IF3 are found in prokaryotes eukaryotes and serve what purpose Bind to 30 s ribosome and prevent 50 s from binding 7 IF2 serves what purpose and used what energy source brings formylated intiator methionine to 30S 8 For what process is the energy used to transfer the methionine to the 30S 9 What purpose does EF Tu serve brings the rest of the aminoacyl tRNAs to the ribosome 10 What does the I in IF1 2 3 and the E in EF Tu stand for Self assessment Lecture 38 Translation a I Initiation b E Elongation 11 What type of enzyme is EF Ts Guanylate exchange factor GEF 12 What purpose does EF G serve this translocase binds and through hydrolysis of GTP moves the mRNA down by 3 NTs 13 Please state the function of release factors These allow release of the nascent peptide from the ribosome 14 Please state the function of the signal recognition peptide This protein binds the signal sequence and brings the ribosome and its mRNA to the ER
View Full Document
Unlocking...