Biotechnology

~~ Marriage of biology & technology ~~ Biotechnology used in industry –Genetic Engineering –Gene Therapy –Stem Cells / Stem Cell Transplant –Genetically Modified Organisms food = plants / animals

Another definition of biotechnology … “The deliberate manipulation of DNA molecules to produce commercial products from living organisms.“ –Scientists are learning how to transfer genes from one animal, plant, or other organism into another

Importance to you …? Food / Crop yield Medicine / Health Issues Disease / illness – transplants Vaccines Livestock Law Enforcement (DNA Fingerprinting) Bioremediation

Mouse: Mus musculus

LE 21-3 Fertilized egg of a frogTadpole hatching from egg Fertilized frog eggs: one week

Restriction enzymes: DNA Scissors RestrictionRestrictionRestriction

Microarray – Gene Chip Can determine thousands of different genes at one time

LE 20-8 Cathode Power source Anode Mixture of DNA molecules of differ- ent sizes Gel Glass plates Longer molecules Shorter molecules

Human Gene Therapy Gene therapy is changing / putting in “good” genes Gene therapy works best when disease is caused by only one defective gene Vectors (viruses) are used for delivery of genes into cells

LE Cloned gene Retrovirus capsid Bone marrow cell from patient Inject engineered cells into patient. Insert RNA version of normal allele into retrovirus. Viral RNA Let retrovirus infect bone marrow cells that have been removed from the patient and cultured. Viral DNA carrying the normal allele inserts into chromosome. Bone marrow

Forensic Evidence DNA “fingerprints” from samples of body fluids or tissue can provide evidence in criminal and paternity cases A DNA fingerprint is a specific pattern of bands

LE Defendant’s blood (D) Blood from defendant’s clothes Victim’s blood (V)

Environmental Cleanup ”Bioremediation” Genetic engineering can be used to design bacteria to clean up oil spills Some bacteria can be used to degrade potentially toxic waste materials

Agricultural Applications DNA technology is being used to improve agricultural productivity and food quality

Animal Husbandry and “Pharm” Animals Transgenic organisms are made by introducing genes from one organism into the genome of another organism Pharmaceutical “factories,” producers of antibiotics

Safety and Ethical Questions Raised by DNA Technology Potential benefits of genetic engineering must be weighed against potential hazards of creating harmful products or procedures Most public concern is about: –genetically modified (GM) organisms

Reproductive Cloning of Mammals In 1997, Scotland – Dolly was the first mammal cloned (a lamb) –from a differentiated mammary cell Dolly’s premature death in 2003, as well as her arthritis, led to speculation that her cells were “older” than those of a normal sheep

LE 21-7 Mammary cell donor Egg cell donor Egg cell from ovary Nucleus removed Cells fused Cultured mammary cells are semistarved, arresting the cell cycle and causing dedifferentiation Nucleus from mammary cell Early embryo Grown in culture Implanted in uterus of a third sheep Surrogate mother Embryonic development Lamb (“Dolly”) genetically identical to mammary cell donor

Since 1997, cloning has been demonstrated in many mammals, including: –Mice –Cats –Cows –Horses –Pigs “Copy Cat” was the first cat cloned Cloning

“Copy Cat”

The Stem Cells of Animals A stem cell is an unspecialized (undifferentiated) cell that can reproduce itself indefinitely and differentiate into specialized cells of several types

LE 21-9 Embryonic stem cellsAdult stem cells Pluripotent cells Totipotent cells Cultured stem cells Different culture conditions Different types of differentiated cells Liver cellsNerve cellsBlood cells

HUMAN GENOME PROJECT

Human Genome Project 13-year project coordinated by the U.S. Department of Energy and the NIH GOALS: –identify the 20,000-25,000 genes in human DNA –determine the sequences of the 3 billion base pairs –address the ethical, legal, and social issues that may arise from the project.

EPIGENETICS You are more than your DNA

University of Utah enetics/intro/ enetics/intro/

bin/hgTracks?hgS_doOtherUser=submit& hgS_otherUserName=Kate&hgS_otherUs erSessionName=encodePortalSessionhttp://genome.ucsc.edu/cgi- bin/hgTracks?hgS_doOtherUser=submit& hgS_otherUserName=Kate&hgS_otherUs erSessionName=encodePortalSession

NIH - Epigenomics

Epigenome Project

Hox Genes Help lay out the basic body forms of many animals –EX: humans, flies, and worms. They set up the head-to-tail organization. You can think of them as direct instructions as an embryo develops: –“Put the head here! Legs go over there!”

Identity of Body Parts Drosophila has master regulatory genes called homeotic genes = HOX Genes Mutations to homeotic genes produce flies with strange traits, such as legs growing from the head in place of antennae

LE Eye Antenna Leg Wild typeMutant

LE 21-14a Head Tail Wild-type larva Mutant larva (bicoid) Drosophila larvae with wild-type and bicoid mutant phenotypes

Widespread Conservation of Developmental Genes Among Animals Analysis of the hox genes in fruit flies has shown that they all include a sequence called a homeobox An very similar sequence has been discovered in both vertebrates and invertebrates

LE Adult fruit fly Fruit fly embryo (10 hours) Fly chromosome Mouse chromosomes Mouse embryo (12 days) Adult mouse

LE ThoraxAbdomen Genital segments ThoraxAbdomen

The End