Lecture Objectives Define Terms Transcription Translation nucleic acid

Lecture Objectives Define Terms: Transcription, Translation, nucleic acid, amino acid, DNA, RNA, m. RNA, c. DNA, “ATCG”, Gene, Genomics, Protein, Proteomics, Exon, Intron, Chromosome, Nucleus, Ribosome, Diploid, Codon, UTR. Explain Concepts: 1) 2) 3) 4) 5) 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.

CAGGACCATGGAACTCAGCGTCCTCCTCTTCCTTGCACTCCTCACAGGACTCTTGCTAC TCCTGGTTCAGCGCCACCCTAACACCCATGACCGCCTCCCACCAGGGCCCCGCCCTCT GCCCCTTTTGGGAAACCTTCTGCAGATGGATAGAAGAGGCCTACTCAAATCCTTTCTGA GGTTCCGAGAGAAATATGGGGACGTCTTCACGGTACACCTGGGACCGAGGCCCGTGGT CATGCTGTGTGGAGTAGAGGCCATACGGGAGGCCCTTGTGGACAAGGCTGAGGCCTTC TCTGGCCGGGGAAAAATCGCCATGGTCGACCCATTCTTCCGGGGATATGGTGTGATCTT TGCCAATGGAAACCGCTGGAAGGTGCTTCGGCGATTCTCTGTGACCACTATGAGGGAC TTCGGGATGGGAAAGCGGAGTGTGGAGGAGCGGATTCAGGAGGAGGCTCAGTGTCTG ATAGAGGAGCTTCGGAAATCCAAGGGGGCCCTCATGGACCCCACCTTCCTCTTCCAGT CCATTACCGCCAACATCATCTGCTCCATCGTCTTTGGAAAACGATTCCACTACCAAGAT CAAGAGTTCCTGAAGATGCTGAACTTGTTCTACCAGACTTTTTCACTCATCAGCTCTGTA TTCGGCCAGCTGTTTGAGCTCTTCTCTGGCTTCTTGAAATACTTTCCTGGGGCACACAG GCAAGTTTACAAAAACCTGCAGGAAATCAATGCTTACATTGGCCACAGTGTGGAGAAG CACCGTGAAACCCTGGACCCCAGCGCCCCCAAGGACCTCATCGACACCTGCTCC ACATGGAAAAAGAGAAATCCAACGCACACAGTGAATTCAGCCACCAGAACCTCAACCT CAACACGCTCTTCTTTGCTGGCACTGAGACCACCAGCACCACTCTCCGCTACG GCTTCCTGCTCAAATACCCTCATGTTGCAGAGTCTACAGGGAGATTGAA CAGGTGATTGGCCCACATCGCCCTCCAGAGCTTCATGACCGAGCCAAAATGCCATACA CAGAGGCAGTCATCTATGAGATTCAGAGATTTTCCGACCTTCTCCCCATGGGTGTGCCC CACATTGTCACCCAACACACCAGCTTCCGAGGGTACATCATCCCCAAGGACACAGAAG TATTTCTCATCCTGAGCACTGCTCTCCATGACCCACACTA

Central Dogma of Molecular Biology: DNA acts as a template to replicate itself DNA is also TRANSCRIBED into RNA is TRANSLATED into Protein

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.

Human Genome: 1 st 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 >100, 000 proteins from 35, 000 genes (only 1. 5% of the genome are “genes”) Each gene can encode multiple proteins due to “alternative splicing”.

DNA Transcription hn. RNA Splicing m. RNA Translation Protein

Steps in Transcription: Promoter region 1) Double-stranded DNA (gene) is separated into single strands. 2) RNA Polymerases make exact RNA template from DNA (hn. RNA). 3) Introns are spliced out of hn. RNA to make m. RNA. 4) Poly-A tail is added to 3’ end of m. RNA. “poly-A tail” 5) m. RNA moves out of nucleus to ribosome (in the cytosol) where protein translation occurs (protein from m. RNA template). Un. Translated Regions (UTR) 3’ UTR before translation start site 5’ UTR after translation stop site 100 -300 “A”

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). Protein Dogma: Sequence of amino acids confers specific 3 D characteristics correlates with function

Depiction of a protein in 3 D

Protein TRANSLATION from m. RNA The genetic “bit” information to encode a specific amino acid is contained in a gene’s 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.

THEREDCATWASNOTHOTBUTWASWETANDMADYETSADBUT THEFOXGOTWETANDATEHIM THEREDCAT_HSDKLSD_WASNOTHOTBUT_WKKNASDN KSAOJ. ASDNALKS_WASWET_ASDFLKSDOFIJEIJKNAW DFN_ANDMAD_WERN. JSNDFJN_YETSAD_MNSFDGPOIJ D_BUTTHEFOX_SDKMFIDSJIR. JER_GOTWET_JSN. DFOI AMNJNER_ANDATEHIM.

Start with a thin 2 x 4 lego block… Add a 2 x 2 lego block… Add a 2 x 3 lego block… Add a 2 x 4 lego block…

4 points of molecular information control 1) Transcriptional 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 of the amount of protein made from m. RNA. 4) Protein Activity Control of how a protein’s activity.