13. Translation of mRNA Flashcards
the process in which the sequence of codons within mRNA provides the information to synthesize the sequence of amino acids that constitute a polypeptide.
Translation
genes that produce mRNA and encode polypeptides
Protein-Coding (Structural) Genes
a type of RNA that is transcribed from a protein-encoding gene and contains the information for the synthesis of a polypeptide.
messenger RNA (mRNA)
a human genetic disorder involving the accumulation of homogentisic acid in the body due to a lack of the enzyme homogentisic acid oxidase.
Alkaptonuria
a genetic disease that involves a defect in a metabolic enzyme.
Inborn Error of Metabolism
the idea, which later needed to be expanded, that one gene encodes one enzyme.
One-Gene/One-Enzyme Hypothesis
a linear sequence of amino acids that is the product of mRNA translation. One or more polypeptides fold and associate with each other to form a functional protein.
Polypeptide
a functional unit composed of one or more polypeptides.
Protein
the correspondence between a codon (i.e., a sequence of three bases in an mRNA molecule) and the functional role that the codon plays during translation. Each codon specifies a particular amino acid or the end of translation.
Genetic Code
a codon that encodes a specific amino acid.
Sense Codon
a three-base sequence in mRNA that initiates translation. It is usually 5′-AUG-3′ and encodes methionine.
Start Codon
a three-base sequence in mRNA that signals the end of translation of a polypeptide. The three stop codons are 5′–UAA–3′, 5′–UAG–3′, and 5′–UGA–3′.
Stop (Termination, Nonsense) Codon
in an mRNA, the region at the 5′ end that precedes the codons that are translated into an amino acid sequence within a polypeptide.
5’-Untranslated Region
in an mRNA, the region at the 3′ end that follows the codons that are translated into an amino acid sequence within a polypeptide.
3’-Untranslated Region
a three-nucleotide sequence in tRNA that is complementary to a codon in mRNA.
Anticodon
in genetics, this term means that more that one codon specifies the same amino acid. For example, the codons GGU, GGC, GGA, and GGG all specify the amino acid glycine.
Degeneracy
two or more different codons that specify the same amino acid.
Synonymous Codons
a series of codons determined by reading bases in groups of three beginning with the start codon as a frame of reference.
Reading Frame
a nonstandard amino acid that may be incorporated into polypeptides during translation.
Selenocysteine (Sec)
a nonstandard amino acid that may be incorporated into polypeptides during translation.
Pyrrolysine (Pyl)
a covalent bond formed between the carboxyl group in one amino acid in a polypeptide and the amino group in the next amino acid.
Peptide Bond
the location of the first amino acid in a polypeptide. The amino acid at the amino-terminus retains a free amino group that is not covalently attached to the second amino acid.
Amino-Terminus (N-Terminus)