Vpachec3 Week 2
From LMU BioDB 2015
The Genetic Code
- Write out the complementary strand of DNA below the strand shown and be sure to label the 5’ and 3’ ends of the complementary strand.
5’-cgtatgctaataccatgttccgcgtataacccagccgccagttccgctggcggcatttta-3’
- There are six possible reading frames in double-stranded DNA. Using the genetic code, translate all possible reading frames of this DNA sequence, keeping in mind the following rules.
- In RNA, the T becomes a U, so everywhere you see a T in the sequence, read it as a U.
- The genetic code is read in the 5’ to 3’ direction.
- Use the single-letter abbreviations for the amino acids because that is what is commonly used by computer programs.
- Wiki Hint: if you start your line with a single space character, it will appear in the grey box surrounded by the dashed line as shown above.
- Which of the reading frames (if any) of the reading frames you translated is an open reading frame, i.e., does not contain a stop codon?
- By convention, the top strand frames are called +1, +2, +3, reading 5' to 3' and the bottom strand frames are called -1, -2, -3, reading 5' to 3'.
Complementary Strand
3’-gcatacgattatggtacaagcgcatattgggtcggcggtcaaggcgaccgccgtaaaat-5’
RNA +1
5’-cguaugcuaauaccauguuccgcguauaacccagccgccaguuccgcuggcggcauuuua-3’
Amino Acid sequence +1
N-ter- R-M-L-I-P-C-S-A-Y-N-P-A-A-S-S-A-G-G-I-L- C-ter
RNA +2
5’-guaugcuaauaccauguuccgcguauaacccagccgccaguuccgcuggcggcauuuua-3’
Amino Acid sequence +2
N-ter-V-C-STOP-Y-H-V-P-R-I-T-Q-P-P-V-P-L-A-A-F-C-ter
RNA +3
5’-uaugcuaauaccauguuccgcguauaacccagccgccaguuccgcuggcggcauuuua-3’
Amino Acid sequence +3
N-ter-Y-A-N-T-M-F-R-V-STOP-P-S-R-Q-F-R-W-R-H-F-C-ter
RNA -1
5’-uaaaaugccgccagcggaacuggcggcuggguuauacgcggaacaugguauuagcauacg-3’
Amino Acid sequence -1
N-ter-STOP-N-A-A-S-G-T-G-G-W-V-I-R-G-G-T-W-Y-STOP-H-T -C-ter
RNA -2
5’-aaaaugccgccagcggaacuggcggcuggguuauacgcggaacaugguauuagcauacg-3’
Amino Acid sequence -2
N-ter-K-M-P-P-A-E-L-A-A-G-L-Y-A-E-H-G-I-S-I- C-ter
RNA -3
5’-aaaugccgccagcggaacuggcggcuggguuauacgcggaacaugguauuagcauacg-3’
Amino Acid sequence -3
N-ter- K-C-R-Q-R-N-W-R-L-G-Y-T-R-N-M-V-L-A-Y- C-ter
Open Reading Frames
+1, -2 and -3
- these do not contain stop codons