genetic code
genetic code The means by which genetic information in DNA controls the manufacture of specific proteins by the cell. The code takes the form of a series of triplets of bases in DNA, from which is transcribed a complementary sequence of codons in messenger RNA (see transcription). The sequence of these codons determines the sequence of amino acids during protein synthesis. There are 64 possible codes from the combinations of the four bases present in DNA and messenger RNA and 20 amino acids present in body proteins: some of the amino acids are coded by more than one codon, and some codons have other functions (see start codon; stop codon).
First base in codon | Second base in codon | Third base in codon | |||
|---|---|---|---|---|---|
The genetic code | |||||
U | C | A | G | ||
U | UUU Phe | UCU Ser | UAU Tyr | UGU Cys | U |
UUC Phe | UCC Ser | UAC Tyr | UGC Cys | C | |
UUA Leu | UCA Ser | UAA (stop codon) | UGA (stop codon) | A | |
UUG Leu | UCG Ser | UAG (stop codon) | UGG Trp | G | |
C | CUU Leu | CCU Pro | CAU His | CGU Arg | U |
CUC Leu | CCC Pro | CAC His | CGC Arg | C | |
CUA Leu | CCA Pro | CAA Gln | CGA Arg | A | |
CUG Leu | CCG Pro | CAG Gln | CGG Arg | G | |
A | AUU Ile | ACU Thr | AAU Asn | AGU Ser | U |
AUC Ile | ACC Thr | AAC Asn | AGC Ser | C | |
AUA Ile | ACA Thr | AAA Lys | AGA Arg | A | |
AUG Met (start codon) | ACG Thr | AAG Lys | AGG Arg | G | |
G | GUU Val | GCU Ala | GAU Asp | GGU Gly | U |
GUC Val | GCC Ala | GAC Asp | GGC Gly | C | |
GUA Val | GCA Ala | GAA Glu | GGA Gly | A | |
GUG Val | GCG Ala | GAG Glu | GGG Gly | G |
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NEARBY TERMS
genetic code