Human Genetics. Translation of RNA into Protein. Replication. DNA. Transcription. RNA. Nucleus. Translation. Protein. . Cytoplasm. Central Dogma. Human Genome. 3.2 million DNA base pairs 1.5\% encode proteins < = > 98.5\% not protein encoding
Translation of RNA into Protein
3.2 million DNA base pairs
1.5% encode proteins < = > 98.5% not protein encoding
~ 31,000 genes encoding 100,000 - 200,000 proteins
How are 100,000 to 200,000 proteins produced from 31,000 genes?
What is the 98.5% of the human genome that does not encode proteins?
kind of sugar
mRNA transcripts are modified before use as a template for translation:
Splicing - the removing internal sequences
- introns are sequences removed
- exons are sequences remaining
Linus Pauling and Alpha Helix led to model building by Watson and Crick
Codons of two nucleotides:
AA GA CA UA
AG GG CG UG
AC GC CC UC
AU GU CU UU
Can only encode
4 amino acids
Can only encode
16 amino acidsHow Do the mRNA Nucleotides Direct Formation of the Amino Acids in a Protein?
Proteins are formed from 20 amino acids in humans.
AAA AGA ACA AUA AAG AGG ACG AUG
AAC AGC ACC AUC AAU AGU ACU AUU
GAA GGA GCA GUA GAG GGG GCG GUG
GAC GGC GCC GUC GAU GGU GCU GUU
CAA CGA CCA CUA CAG CGG CCG CUG
CAC CGC CCC CUC CAU CGU CCU CUU
UAA UGA UCA UUA UAG UGG UCG UUG
UAC UGC UCC UUC UAU UGU UCU UUU
Allows for 64 potential codons => sufficient!
AGA UCG ACG UUA AGC
arginine - serine - threonine - leucine - serine
AGA UCG CAC GUU AAG C
Corresponding to the protein:
arginine - serine - histidine - valine – lysine
Initiation - translation begins at start codon (AUG=methionine)
Elongation - the ribosome uses the tRNA anticodon to match codons to amino acids and adds those amino acids to the growing peptide chain
Termination - translation ends at the stop codon
UAA, UAG or UGA
3’- C A T T A G G A G -5’DNA template (antisense) strand
5'- GUA AUC CUC -3'mRNA
N - val - ile - leu - Cprotein
By convention, amino acid sequences are written and numbered left-to-right from N-terminus to C-terminus.
5'-CAU-3'if anticodon is written 5’->3'