Presentation is loading. Please wait.

Presentation is loading. Please wait.

Chapter 14: Protein Synthesis

Published byGustavo Santos Modified over 5 years ago

Similar presentations

Presentation on theme: "Chapter 14: Protein Synthesis"— Presentation transcript:

1 Chapter 14: Protein Synthesis

2 Chapter 14 Protein Synthesis - Overview
The DNA of the gene is transcribed into RNA Which is translated into protein The flow of genetic information from DNA to RNA to Protein is called the CENTRAL DOGMA DNA Transcription RNA Translation Protein

3 Chapter 14 Protein Synthesis (Overview)
Central Dogma - FLOW IS FROM DNA TO RNA TO PROTEIN

4 FLOW IS FROM DNA TO RNA TO PROTEIN
Chapter 14 Protein Synthesis (Overview) FLOW IS FROM DNA TO RNA TO PROTEIN Genes on DNA are expressed through proteins, which provide the molecular basis for inherited traits A particular gene, is a linear sequence of many nucleotides Specifies a polypeptide (long protein made of amino acids)

5 Chapter 14 Protein Synthesis (Overview)
Genes - discrete units of hereditary information comprised of a nucleotide sequence found in a DNA molecule.

6 Messenger (mRNA) Monomer: nucleotide Parts of a mRNA Nucleotide
Ribose Sugar Phosphate Nitrogenous Base Three main differences between mRNA and DNA Ribose instead of deoxyribose mRNA is generally single stranded mRNA has uracil in place of thymine (U instead of T)

7 RNA Three Types of RNA Messenger RNA (mRNA) – carries copies of genes (DNA) to the rest of the cell. Ribosomal RNA (rRNA) – make up the ribosomes. Transfer RNA (tRNA) – transfers the amino acids to the ribosomes as specified by the mRNA

8 TRANSCRIPTION: The process of making mRNA from DNA
Why do you need this process? Location of DNA? Nucleus Location of Ribosome? Cytoplasm mRNA takes code from DNA in the nucleus to the cytoplasm Strand to be transcribed T A C DNA A T G Transcription A U G A A G U U U U A G RNA Start condon Stop condon Translation Polypeptide Met Lys Phe

9 Transcription produces genetic messages in the form of mRNA
A close-up view of transcription RNA polymerase RNA nucleotides Direction of transcription Template Strand of DNA Newly made RNA T C A G U

10 In the nucleus, the DNA helix unzips
And RNA nucleotides line up along one strand of the DNA, following the base pairing rules As the single-stranded messenger RNA (mRNA) peels away from the gene The DNA strands rejoin RNA polymerase RNA nucleotides Direction of transcription Template Strand of DNA Newly made RNA T C A G U

11 Transcription of a gene
RNA polymerase DNA of gene Transcription of a gene Initiation Elongation Termination Promoter DNA Terminator DNA 1 Initiation Area shown In Figure 10.9A 2 Elongation Growing RNA 3 Termination Completed RNA RNA polymerase

12 Eukaryotic mRNA is processed before leaving the nucleus
Exon Intron Exon Intron Exon DNA Cap Transcription Addition of cap and tail RNA transcript with cap and tail Introns removed Tail Exons spliced together mRNA Coding sequence Nucleus Cytoplasm Eukaryotic mRNA is processed before leaving the nucleus Noncoding segments called introns are spliced out leaving only the coding exons A 5’ cap and a poly A tail are added to the ends of mRNA Cap and tail protect mRNA 5’ 3’

13 T C C A A T A U T C T G U G A C C A U C C A C G A A T A G G T T Direction of transcription

14

15 13.2 Translation tRNA molecules Growing polypeptide (protein)
mRNA Small subunit Growing polypeptide (protein) Large subunit

16 Protein Synthesis - Translation
Translation is defined as going from mRNA to protein tRNA which have amino acids attached are going to the ribosome. What are amino acids? monomers of proteins Does the order of amino acids matter? Yes, they must be in order for the protein to fold correctly. How does the correct tRNA (with amino acid attached) bind to the mRNA? The tRNA contains an anticodon which matches up with the mRNA sequence (codon).

17 Transfer RNA (tRNA) molecules serve as interpreters during translation
Takes place in the cytoplasm A ribosome attaches to the mRNA and translates its message into a specific polypeptide aided by transfer RNAs (tRNAs) tRNAs can be represented in several ways Amino acid attachment site Amino acid attachment site Hydrogen bond RNA polynucleotide chain Anticodon Anticodon

18 Translation Each tRNA molecule A specific amino acid
Is a folded molecule bearing a base triplet called an anticodon on one end A specific amino acid Is attached to the other end Amino acid attachment site Anticodon

19 Ribosomes build polypeptides (proteins)
Translation Ribosomes build polypeptides (proteins) A ribosome consists of two subunits Each made up of proteins and a kind of RNA called ribosomal RNA Translation at Ribosome tRNA molecules mRNA Small subunit Growing polypeptide Large subunit

20 Translation The subunits of a ribosome
Hold the tRNA and mRNA close together during translation tRNA-binding sites Large subunit Next amino acid to be added to polypeptide Growing polypeptide tRNA mRNA- binding site mRNA Small subunit Codons

21 An initiation codon marks the start of an mRNA message
mRNA, a specific tRNA, and the ribosome subunits assemble during initiation Met Initiator tRNA 1 2 mRNA Small ribosomal subunit Start codon Large ribosomal subunit A site U A C A U G P site

22 Elongation adds amino acids to the polypeptide chain until a stop codon terminates translation
Once initiation is complete amino acids are added one by one to the first amino acid The mRNA moves a codon at a time A tRNA with a complementary anticodon pairs with each codon, adding its amino acid to the peptide chain

23 Each addition of an amino acid
Occurs in a three-step elongation process Amino acid Polypeptide P site A site Anticodon mRNA Codons 1 Codon recognition mRNA movement Stop codon 2 Peptide bond formation New Peptide bond Figure 10.14 3 Translocation

24 Figure out the exact sequence of amino acids needed
Take the DNA and transcribe it into mRNA Example: TAC ATA CTA GCG ACT mRNA: Take the mRNA sequence and decode it using the codon chart. AUG UAU GAU CGC UGA AUG = MET UAU = TYR GAU = ASP CGC = ARG Animation

25 Mutations Mutations – heritable changes in genetic information (changes to the DNA sequence) Two types - gene and chromosomal mutations Mutations can be caused by chemical or physical agents (mutagens) Chemical – pesticides, tobacco smoke, environmental pollutants Physical – X-rays and ultraviolet light

26 Mutations Gene mutations
Point Mutation: mutations that affect a single nucleotide Frameshift mutation: shift the reading frame of the genetic message. Can change the entire protein so it doesn’t work Gene Mutations Explained

27 Mutations

28 Chromosomal Mutations
Chromosomal mutation: mutation that changes the number or structure of chromosomes.

29 Chromosomal Mutations
Types of chromosomal mutations: Deletion: The loss of all or part of a chromosome Duplication: A segment is repeated Inversion: part of the chromosome is reverse from its usual direction. Translocation: one chromosome breaks off an attaches to another chromosome.

Download ppt "Chapter 14: Protein Synthesis"

Similar presentations

Chapter 17~ From Gene to Protein

Chapter 17~ From Gene to Protein
RNA and Protein Synthesis

RNA and Protein Synthesis
RNA and PROTEIN SYNTHESIS

RNA and PROTEIN SYNTHESIS
Review: The flow of genetic information in the cell is DNA  RNA  protein  The sequence of codons in DNA spells out the primary structure of a polypeptide.

Review: The flow of genetic information in the cell is DNA  RNA  protein  The sequence of codons in DNA spells out the primary structure of a polypeptide.
CHAPTER 10 Molecular Biology of the Gene

CHAPTER 10 Molecular Biology of the Gene
10-2: RNA and 10-3: Protein Synthesis

10-2: RNA and 10-3: Protein Synthesis
Protein Synthesis The genetic code – the sequence of nucleotides in DNA – is ultimately translated into the sequence of amino acids in proteins – gene.

Protein Synthesis The genetic code – the sequence of nucleotides in DNA – is ultimately translated into the sequence of amino acids in proteins – gene.
Transcription Transcription is the synthesis of mRNA from a section of DNA. Transcription of a gene starts from a region of DNA known as the promoter.

Transcription Transcription is the synthesis of mRNA from a section of DNA. Transcription of a gene starts from a region of DNA known as the promoter.
Lesson Overview 13.1 RNA.

Lesson Overview 13.1 RNA.
From DNA to Protein Chapter 14. 14.1 DNA, RNA, and Gene Expression  What is genetic information and how does a cell use it?

From DNA to Protein Chapter DNA, RNA, and Gene Expression  What is genetic information and how does a cell use it?
Protein Synthesis. The DNA Code It is a universal code. The order of bases along the DNA strand codes for the order in which amino acids are chemically.

Protein Synthesis. The DNA Code It is a universal code. The order of bases along the DNA strand codes for the order in which amino acids are chemically.
RNA AND PROTEIN SYNTHESIS RNA vs DNA RNADNA 1. 5 – Carbon sugar (ribose) 5 – Carbon sugar (deoxyribose) 2. Phosphate group Phosphate group 3. Nitrogenous.

RNA AND PROTEIN SYNTHESIS RNA vs DNA RNADNA 1. 5 – Carbon sugar (ribose) 5 – Carbon sugar (deoxyribose) 2. Phosphate group Phosphate group 3. Nitrogenous.
VII RNA and Protein Synthesis

VII RNA and Protein Synthesis
RNA and Protein Synthesis

RNA and Protein Synthesis
FROM DNA TO PROTEIN Transcription – Translation. I. Overview Although DNA and the genes on it are responsible for inheritance, the day to day operations.

FROM DNA TO PROTEIN Transcription – Translation. I. Overview Although DNA and the genes on it are responsible for inheritance, the day to day operations.
What is the job of p53? What does a cell need to build p53? Or any other protein?

What is the job of p53? What does a cell need to build p53? Or any other protein?
Chapter 13. The Central Dogma of Biology: RNA Structure: 1. It is a nucleic acid. 2. It is made of monomers called nucleotides 3. There are two differences.

Chapter 13. The Central Dogma of Biology: RNA Structure: 1. It is a nucleic acid. 2. It is made of monomers called nucleotides 3. There are two differences.
From Gene To Protein Chapter 17. From Gene to Protein The “Central Dogma of Molecular Biology” is DNA  RNA  protein Meaning that our DNA codes our RNA.

From Gene To Protein Chapter 17. From Gene to Protein The “Central Dogma of Molecular Biology” is DNA  RNA  protein Meaning that our DNA codes our RNA.
Transcription & Translation Chapter 17 (in brief) Biology – Campbell Reece.

Transcription & Translation Chapter 17 (in brief) Biology – Campbell Reece.
12-3 RNA and Protein Synthesis

12-3 RNA and Protein Synthesis

Similar presentations

Ads by Google