Genes and Proteins

modified guanine added to the 5' end of pre-mRNAs to protect mRNA from degradation and assist translation

• 5' cap
• degeneracy (of the genetic code)
• codon
• peptidyl transferase

enzyme that "charges" tRNA molecules by catalyzing a bond between the tRNA and a corresponding amino acid

• aminoacyl tRNA synthetase
• promoter
• reading frame
• codon

three-nucleotide sequence in a tRNA molecule that corresponds to an mRNA codon

• anticodon
• plasmid
• signal sequence
• intron

states that genes specify the sequence of mRNAs, which in turn specify the sequence of proteins

• central dogma
• template strand
• poly-A tail
• polysome

three consecutive nucleotides in mRNA that specify the insertion of an amino acid or the release of a polypeptide chain during translation

• codon
• reading frame
• upstream
• rho-independent

describes that a given amino acid can be encoded by more than one nucleotide triplet; the code is degenerate, but not ambiguous

• degeneracy (of the genetic code)
• central dogma
• signal sequence
• polysome

nucleotides following the initiation site in the direction of mRNA transcription; in general, sequences that are toward the 3' end relative to a site on the mRNA

• downstream
• start codon
• Shine-Dalgarno sequence
• degeneracy (of the genetic code)

sequence present in protein-coding mRNA after completion of pre-mRNA splicing

• exon
• degeneracy (of the genetic code)
• Shine-Dalgarno sequence
• downstream

nonessential eukaryotic promoter sequence that binds cellular factors to increase the efficiency of transcription; may be present several times in a promoter

• GC-rich box (GGCG)
• central dogma
• start codon
• rho-independent

structure of RNA when it folds back on itself and forms intramolecular hydrogen bonds between complementary nucleotides

• hairpin
• transcription bubble
• start codon
• rho-dependent termination