RNA & Protein Synthesis
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Transcript of RNA & Protein Synthesis
One gene=one protein
RNA & Protein Synthesis
Genetic Code -UniversalAll living organisms have the same four
nucleotides- A, C, T, & GCentral Dogma:
Information flows from DNA RNA ProteinRNA- Ribonucleic Acid
1 single chain of nucleotidesRNA nucleotide- 3 parts
Sugar- ribosePhosphate groupNitrogen base
Adenine, Guanine, Cytosine, Uracil (instead of thymine)
3 types of RNA- mRNA; tRNA; rRNABase pairing rules: A-U
C-G
Triplet Code:There are 20 amino acids-
4 nucleotides must combine in
groups of three.64 codons- (43)
61 code for amino acids.
3 are “stop codons”There is one start
codon- AUG- methionine
mRNA codon chart
Protein Synthesis- 2 main steps:
1. Transcription- occurs in nucleusmRNA( messenger RNA) is made from
DNA.mRNA leaves the nucleus.DNA stays in the nucleus.
2. Translation- occurs at the ribosomesmRNA codons are translated into
proteins.
Overview protein synthesis steps:
Details, details, details……..Transcription-
DNA molecule separates; one chain serves as a template.
Base pair rules apply- A-U; C-GmRNA (after editing) goes to the ribosomes.
Translation-mRNA is read by the ribosome.Translation begins with the start codon- AUG rRNA (ribosomal RNA) holds the mRNA in the ribosome.tRNA (transfer RNA) brings the correct amino acid.tRNA is T shaped:
At one end- anticodon ( grouping of 3 RNA nucleotides) that matches up with the mRNA. (base pair rules)
Opposite end -correct amino acid.Each tRNA is specific for only one amino acid.
Details continued……..Amino acids combine to form a protein.The ribosome reads the mRNA code until a
“stop” codon.Then the ribosome releases the mRNA and the
protein is released.Very fast process- occurs in less than 1 minute.
3 nucleotide terms: DNA= triplet codemRNA= codontRNA= anticodon
Review: mRNA codon chart to determine the amino acids.
mRNA Codon Chart