Download Genetic engineering

Principles of genetic engineering
Lec:1
Stage:1
Syllabus:
1.Introduction and Molecular definitions
2.The structural organization of eukaryotic chromosome
3.Molecular Structure of DNA and RNA
4.DNA replication
5.Mid exam
6.Gene structure
7.Central dogma: Transcription, Translation
8.Regulation
9.Recombinant DNA Technology : Restriction enzymes
10.Gene cloning using vectors
11.Transformation
12.Hosts
13.DNA amplification
14.Gel electrophoresis technique
15.Applications of genetic engineering
References:
1. Anderson M. 2012. A closer look at genes and genetic engineering.
Britannica Educational Publishing.
2. Brooker, Robert J.2012.GENETICS: ANALYSIS & PRINCIPLES,
4thed. McGraw-Hill Companies, Inc.,1221Avenue of the Americas,
New York, NY 10020.
3. Glick, B.R., Pasternak, J.J. and Patten, C.L.2010.Molecular
Biotechnology, 4th ed. ASM Press, 1752 N St. NW, Washington,
DC 20036-2904, USA.
4. Larramendy M.L.and Soloneski S.2016. Nucleic Acids from Basic
Aspects to Laboratory Tools.1sted. ExLi4EvA Publishing.
5. Misra, A.K. 2011.Fundamentals of Cell and Molecular Genetics.
Panima Publishing Corporation, New Delhi.
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1. Introduction:
1.1.What is genetic engineering?
Genetic engineering: is a process where genetic material (DNA) is
taken from one organism and inserted into the cells of another organism.
Also, can be the rearrangement of gene location or the removal of genes.
The “altered” organism then makes new substances or performs new
functions based on its new DNA. For example, the protein insulin, used
in the treatment of diabetes, now can be produced in large quantities by
genetically engineered bacteria and yeasts. Insulin was formerly extracted
from pigs or cows.
1.2 What can genetic engineering do?
1- Improve organism ability to do something it already does. For
example, an adjustment in the amino acid balance in a particular corn
variety improves the corn’s ability to be stored.
2- Suppress or stop organism from doing something it already does. For
example, the gene that codes for the softening of tomatoes is “turned off”
in a genetically engineered tomato variety so the tomatoes do not soften
as quickly.
3- Make organism do something new. For example, particular bacteria
and yeasts have been genetically engineered to produce chymosin, an
enzyme used in cheese production.
1.3 What are the basic procedures for producing a genetically
engineered product?
The actual procedures for producing a genetically engineered product are
very complex. However, most genetically engineered products are
produced using the basic steps described below:
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a) Trait identification: Traits of organisms are identified.
b) Gene discovery: Genes for the desired traits are identified.
c) Gene cloning: The desired gene is inserted into a bacterial cell and, as
bacteria reproduce, the desired gene is also reproduced.
d) Gene verification: Researchers study the copies of the gene using
molecular techniques to verify that the replicated gene is precisely what is
wanted.
e) Gene implantation: Using a bacterium or other procedure, the desired
gene is transferred into the chromosomes of the host cells.
f) Cell regeneration: Researchers select the host cells that contain the
new gene and regenerate whole organism from the selected host cells.
g) The new organism testing: Laboratory and field-testing occur to verify
the function and safety of the new organism.
h) Cell proliferation: Cells with the desired traits are produced using
standards set for specific cell production.
2. Molecular definitions:
Chromosomes: An aggregates of DNA and protein found in every living
thing. It is a packaged and organized structure containing most of
the DNA of a living organism. Most eukaryotic cells have a set of
chromosomes (46 in humans) with the genetic material spread among
them. In prokaryotic cells, chromosome free-floating in cytoplasm.
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DNA: Is the genetic material of living organisms is composed of a
substance called deoxyribonucleic acid, abbreviated DNA. It is stores the
information needed for the synthesis of all cellular proteins. In other
words, the main function of the genetic blueprint is to code for the
production of cellular proteins in the correct cell, at the proper time, and
in suitable amounts. This is an extremely complicated task because living
cells make thousands of different proteins. DNA’s ability to store
information is based on its structure. It is composed of a linear sequence
of nucleotides. Each nucleotide contains one of four nitrogen bases:
adenine (A), thymine (T), guanine (G), or cytosine (C). The linear order
of these bases along a DNA molecule contains information similar to the
way that groups of letters of the alphabet represent words. For example,
the “meaning” of the sequence of bases ATGGGCCTTAGC differs from
that of TTTAAGCTTGCC.
DNA Sequence
ATG GGC
Amino Acid Sequence
CTT
AGC
Phenylalanine
Lysine
Leucine
Alanine
TTT AAG CTT
GCC
Methionine
Glycine
Leucine
Serine
So that, the DNA considered, the molecule of life. For example,
human body have trillions of cells. Each cell contains:
46 human chromosomes, found in 23 pairs, then 2 meters of DNA
Approximately 3 billion DNA base pairs per set of chromosomes,
containing the bases A, T, G, and C , Approximately 20,000 to 25,000
genes coding for proteins that perform most life functions ( Figure 1).
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Figure 1: The DNA found in the cell nucleus of the complete set of human
chromosomes. People have two sets of chromosomes, one from each parent.
Collectively, each set of chromosomes is composed of a DNA sequence that is
approximately 3 billion nucleotide base pairs long. Estimates suggest that each set
contains about 20,000 to 25,000 different genes. Most genes encode proteins.
Genetics: Is the branch of biology that deals with heredity and variation.
It allowing us to understand how life can exist at all levels of complexity
and its continuity from generation to generation, ranging from the
molecular to the population level. Genetic variation is the root of the
natural diversity that we observe among members of the same species as
well as among different species. DNA sequences within most genes
contain the information to direct the order of amino acids within
polypeptides according to the genetic code. In the code, a three-base
sequence specifies one particular amino acid among the 20 possible
choices. One or more polypeptides form a functional protein. In this way,
the DNA can store the information to specify the proteins made by an
organism.
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What is a gene?
Genes are sequences of DNA, which serve as blueprints for the
production of proteins in all living things.
DNA is found in all cells, usually in the nuclei. In bacteria and viruses,
which do not have nuclei, the DNA floats within the cell. DNA is
composed of six molecules: sugars, phosphates and four bases. A gene
produces a specific protein or has an assigned function.
Gene: The molecular unit of an organism that contains information for a
specific trait (specific DNA sequence), and it is a segment of DNA that
produces a functional product. The functional product of most genes is a
polypeptide, which is a linear sequence of amino acids that folds into
units that constitute proteins.
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Genome: An entire set of genes for an organism. It is the genetic
material of an organism and consists of DNA (or RNA in RNA viruses).
The genome includes both the genes, (the coding regions), the noncoding
DNA and the genomes of the mitochondria and chloroplasts.
GMO: Acronym for genetically modified organism. It is any organism
whose genetic material has been altered using genetic engineering
techniques (i.e., a genetically engineered organism).
Heredity: a A process within genes are passed on from one generation to
the next.
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Nucleotides: Are organic molecules that serve as the monomers, or
subunits,
of nucleic
acids like DNA
(deoxyribonucleic
acid)
and RNA (ribonucleic acid). The building blocks of nucleic acids,
nucleotides
are
composed
of
a nitrogenous
base,
a five-carbon
sugar (ribose or deoxyribose), and at least one phosphate group. Thus,
anucleoside plus a phosphate group yields a nucleotide.
Plasmid: The circular DNA structure used by bacteria. It is a
small DNA molecule within a cell that is physically separated from
a chromosomal DNA and can replicate independently.
Protein: Large biomolecules used by an organism for a number of
purposes; in this context, to express a desired trait.
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Recombinant DNA(rDNA): DNA molecules formed by laboratory
methods of genetic recombination (such as molecular cloning) to bring
together genetic material from multiple sources, creating sequences that
would not otherwise be found in the genome.
Restriction enzyme: An enzyme that "cuts" DNA when specific base
pair sequences are present.
Trait:
A
distinguishing
characteristic.
characteristics of organisms.
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Genes
involving
with