Biology 135A Gene Expression (Ch. 17)

Biology 135A Gene Expression (Ch. 17)

• Course material outlines include gene discovery, the genetic code, transcription, RNA modification, and translation.
• A diagram shows the process of transcription and translation, depicting DNA, RNA, and protein.
• The genetic code uses a triplet code with 64 codons.
• Template and non-template DNA strands are part of the genetic code.
• mRNA is synthesized and translated in the 5' to 3' direction.
• A codon chart illustrates the genetic code, with codons corresponding to specific amino acids.
• The genetic code is degenerate, and synonymous codons exist for some amino acids.
• The genetic code is universal.
• Eukaryotic RNA processing involves capping and tailing, export, protection, and translation initiation.
• A modified guanine nucleotide is added to the 5' end, while 50-250 adenine nucleotides are added to the 3' end.
• Eukaryotic RNA splicing cuts out introns and splices together exons.
• Spliceosomes and exon-domain relationships are part of RNA processing.
• Alternative splicing allows 20,000 genes to produce hundreds of thousands of proteins.
• Translation's major players include mRNA, tRNA, amino acids, aminoacyl tRNA synthetases, ribosomes, and polypeptides.
• tRNA is a single-stranded molecule with an acceptor stem, anticodon, and wobble base pairing.
• Aminoacyl-tRNA synthetase enzymes combine specific amino acids with corresponding tRNAs.
• Ribosomes have small and large subunits with P, A, and E sites for protein synthesis.
• Translation initiation involves an initiator tRNA (methionine), mRNA binding site, and ribosomal subunits.
• Translation elongation involves codon recognition, peptide bond formation, and translocation of the ribosome.
• Translation termination involves a stop codon and release factors.
• Protein folding and targeting follow a process beginning in the cytosol. The signal peptide halts protein synthesis, the SRP binds to a receptor protein, polypeptide synthesis then resumes as the protein moves through the membrane, the signal peptide is cleaved, and the rest of the polypeptide folds.
• Polyribosomes are multiple ribosomes translating the same mRNA molecule simultaneously.
• Bacterial transcription and translation are coupled.
• mRNA vaccines utilize mRNA instructions to guide your body in creating proteins resembling parts of a virus. This allows your body to build immunity without causing the virus.

Explore the intricacies of gene expression in Biology 135A. This quiz covers key topics including gene discovery, transcription, RNA modification, and the translation process with a focus on the genetic code and its codons. Test your understanding of eukaryotic RNA processing and the roles of various molecular components involved in gene expression.