Lecture Objectives

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• Lecture Objectives
• Define Terms
• Transcription, Translation, nucleic acid, amino
  acid, DNA, RNA, mRNA, cDNA, ATCG, Gene,
  Genomics, Protein, Proteomics, Exon, Intron,
  Chromosome, Nucleus, Ribosome, Diploid, Codon,
  UTR.
• Explain Concepts
• How 24,000 genes in the human genome encode more
  than 100,000 proteins.
• How information flows through Transcription and
  Translation.
• 4 points of information control in the cell.
• Explain RNA splicing with respect to Exons and
  Introns.
• Explain the difference between a Haploid and a
  Diploid Cell.

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CAGGACCATGGAACTCAGCGTCCTCCTCTTCCTTGCACTCCTCACAGGAC
TCTTGCTACTCCTGGTTCAGCGCCACCCTAACACCCATGACCGCCTCCCA
CCAGGGCCCCGCCCTCTGCCCCTTTTGGGAAACCTTCTGCAGATGGATAG
AAGAGGCCTACTCAAATCCTTTCTGAGGTTCCGAGAGAAATATGGGGACG
TCTTCACGGTACACCTGGGACCGAGGCCCGTGGTCATGCTGTGTGGAGTA
GAGGCCATACGGGAGGCCCTTGTGGACAAGGCTGAGGCCTTCTCTGGCCG
GGGAAAAATCGCCATGGTCGACCCATTCTTCCGGGGATATGGTGTGATCT
TTGCCAATGGAAACCGCTGGAAGGTGCTTCGGCGATTCTCTGTGACCACT
ATGAGGGACTTCGGGATGGGAAAGCGGAGTGTGGAGGAGCGGATTCAGGA
GGAGGCTCAGTGTCTGATAGAGGAGCTTCGGAAATCCAAGGGGGCCCTCA
TGGACCCCACCTTCCTCTTCCAGTCCATTACCGCCAACATCATCTGCTCC
ATCGTCTTTGGAAAACGATTCCACTACCAAGATCAAGAGTTCCTGAAGAT
GCTGAACTTGTTCTACCAGACTTTTTCACTCATCAGCTCTGTATTCGGCC
AGCTGTTTGAGCTCTTCTCTGGCTTCTTGAAATACTTTCCTGGGGCACAC
AGGCAAGTTTACAAAAACCTGCAGGAAATCAATGCTTACATTGGCCACAG
TGTGGAGAAGCACCGTGAAACCCTGGACCCCAGCGCCCCCAAGGACCTCA
TCGACACCTACCTGCTCCACATGGAAAAAGAGAAATCCAACGCACACAGT
GAATTCAGCCACCAGAACCTCAACCTCAACACGCTCTCGCTCTTCTTTGC
TGGCACTGAGACCACCAGCACCACTCTCCGCTACGGCTTCCTGCTCATGC
TCAAATACCCTCATGTTGCAGAGAGAGTCTACAGGGAGATTGAACAGGTG
ATTGGCCCACATCGCCCTCCAGAGCTTCATGACCGAGCCAAAATGCCATA
CACAGAGGCAGTCATCTATGAGATTCAGAGATTTTCCGACCTTCTCCCCA
TGGGTGTGCCCCACATTGTCACCCAACACACCAGCTTCCGAGGGTACATC
ATCCCCAAGGACACAGAAGTATTTCTCATCCTGAGCACTGCTCTCCATGA
CCCACACTA
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Central Dogma of Molecular Biology DNA acts as
a template to replicate itself DNA is also
TRANSCRIBED into RNA RNA is TRANSLATED into
Protein
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Human Genome Diploid (2 copies of genetic
material) 46 Chromosomes (total) Gender-specific
Chromosomes XX Female XY Male Not all
cells/organisms are diploid gametes
haploid (1 copy) wheat, corn hexaploid (6
copies) Chromosome literally means color And
body described by early microscopists referring
to the subcellular structures that stained by
some dyes.
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Human Genome 1st Sequenced (Published) in
February 2001 Over 3 Billion base
pairs Estimated 35,000 genes (20 have been
patented!). Genes defined as regions of the
genome that encode RNA that are translated into
proteins. Estimated gt100,000 proteins from
35,000 genes (only 1.5 of the genome are
genes) Each gene can encode multiple proteins
due to alternative splicing.
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DNA hnRNA mRNA Protein
Transcription
RNA Splicing
Translation
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Promoter region
Steps in Transcription 1) Double-stranded DNA
(gene) is separated into single strands. 2) RNA
Polymerases make exact RNA template from DNA
(hnRNA). 3) Introns are spliced out of hnRNA to
make mRNA. 4) Poly-A tail is added to 3 end of
mRNA. 5) mRNA moves out of nucleus to ribosome
(in the cytosol) where protein translation occurs
(protein from mRNA template).
poly-A tail
UnTranslated Regions (UTR) 3 UTR before
translation start site 5 UTR after translation
stop site
100-300 A
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Protein The structural, functional and
secreted stuff The stuff you are made
of skin, hair, cartilage, tendons, eye color,
etc. where genetic information is translated
into function Made up of 20 different amino
acids that each harbor different molecular
characteristics (soluble, insoluble, acidic,
basic, etc, etc).
Protein Dogma Sequence of amino acids confers
specific 3D characteristics 3D characteristics
correlates with function
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Depiction of a protein in 3D
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(No Transcript)
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Protein TRANSLATION from mRNA The genetic bit
information to encode a specific amino acid is
contained in a genes Codon. A Codon is a 3-base
(3-nucleotide) sub-sequence that defines the
amino acid to be incorporated into the
protein. All proteins start with the Codon ATG
(DNA notation) or AUG (RNA), which encodes for
the amino acid Methionine. This start or
initiation codon sets the Reading Frame for
Translation. Many genetic mutations involve the
deletion of a single nucleotide, which causes a
Frame Shift (aka Frame Shift Mutation),
disrupting the Translational process causing a
change in the amino acid composition and alters
the stop codon for all amino acids Down stream
from this type of mutation.
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(No Transcript)
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THEREDCATWASNOTHOTBUTWASWETANDMADYETSADBUTTHEFOXGO
TWETANDATEHIM
THEREDCAT_HSDKLSD_WASNOTHOTBUT_WKKNASDNKSAOJ.ASDNA
LKS_WASWET_ASDFLKSDOFIJEIJKNAWDFN_ANDMAD_WERN.JSND
FJN_YETSAD_MNSFDGPOIJD_BUTTHEFOX_SDKMFIDSJIR.JER_G
OTWET_JSN.DFOIAMNJNER_ANDATEHIM.
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Start with a thin 2 x 4 lego block
Add a 2 x 2 lego block
Add a 2 x 3 lego block
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4 points of molecular information control
1) Transcriptional Control Control of which
genes are used or expressed by the cell. 2)
RNA Processing or Splicing Editing out of
introns and sometimes key exons. 3)
Translational Control Control of the amount of
protein made from mRNA. 4) Protein Activity
Control Control of how a proteins activity.