Algorithmic Foundations of Computational Biology: Course 3

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Algorithmic Foundations of Computational Biology
Course 3

• Central Dogma of Molecular Biology
• http//www.ncbi.nlm.nih.gov/Class/MLACourse/Mod
  ules/MolBioReview/

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Central Dogma of Molecular Biology
"The central dogma of biology states that the
coded genetic information hard-wired into DNA is
transcribed into individual transportable
cassettes, composed of messenger RNA (mRNA)
each mRNA cassette contains the program for
synthesis of a particular protein (or small
number of proteins)."
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Central Dogma of Molecular Biology

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Central Dogma of Molecular Biology
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The Human Genome
A genome is all the DNA contained in an organism
or a cell, which includes the chromosomes plus
the DNA in mitochondria
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DNA
DNA  the chemical inside the nucleus of a cell
that carries the genetic instructions for making
living organisms. DNA sequencing  Determining
the exact order of the base pairs in a segment
of DNA.
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GeneA gene is the functional and physical unit
of heredity passed from parent to offspring.
Genes are pieces of DNA, and most genes contain
the information for making a specific protein.
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Regulatory Genomics
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mRNA
When DNA is first transcribed into RNA, the
primary transcript includes both exons and
introns. Before moving out of the nucleus into
the cytoplasm, the RNA goes through a splicing
process that removes the introns and splices the
exons together, forming the mature mRNA that
will be used for the translation process into
the final protein.
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Translation Translation is the
process of translating the sequence of nucleotide
bases in DNA/RNA into a sequence of amino acids
in a protein.
Start and Stop Codons
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ProteinA protein is a large complex
molecule made up of one or more chains of amino
acids. Proteins perform a wide variety of
activities in the cell. Amino acids are a group
of 20 different kinds of small molecules that
link together in long chains to form proteins.
Often referred to as the "building blocks" of
proteins.
Protein
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The 20 Amino Acids

• Ala     A       Alanine        
• Arg     R       Arginine        
• Asn     N       Asparagine        
• Asp     D       Aspartic acid (Aspartate)
         
• Cys     C       Cysteine        
• Gln     Q       Glutamine        
• Glu     E       Glutamic acid (Glutamate)
         
• Gly     G       Glycine        
• His     H       Histidine        
• Ile     I       Isoleucine        
• Leu     L       Leucine        
• Lys     K       Lysine        
• Met     M       Methionine        
• Phe     F       Phenylalanine        
• Pro     P       Proline        
• Ser     S       Serine        
• Thr     T       Threonine        
• Trp     W       Tryptophan        
• Tyr     Y       Tyrosine        

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Alignment
Multiple sequence alignment showing conserved
residues (amino acids) in the DNA mismatch
repair domain. The aligned sequences are from
various organisms, including human,
Synechocystis sp. (a bacterium), mouse, fruit
fly, Thermotoga maritima (a bacterium),
Arabidopsis thaliana (a plant),Borrelia
burgdorferi (a bacterium), and baker's yeast.