Techniques in molecualr genetics

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Transcript of Techniques in molecualr genetics

Muhammad Hassan4031

Mr. Danish Riaz Lecturer of Zoology Govt. Postgraduate

College ,Samanabad Faisalabad

• Definition:- It is a branch of genetics that

studied with the structure and functions of gene at molecular level.

There are following techniques in molecular genetics.

• Amplification• Separation and detection• Gene expression

• There are following methods for amplification

1.Polymerase chain reaction(PCR)2.Cloning DNA in bacteria

• The following materials are used in Polymerase chain reaction

1. DNA nucleotides2. Template DNA3. Primers4. Taq polymerase

DNA nucleotide are the base for new DNA Template DNA is specifically amplified Primers are the complimentry nucleotides

that can go on the eithr side of template DNA

Taq polymerase is heat stabe enzyme that start the production at high temprature

At high temprature DNA is denature into single standard b breaking hydrogen bonds

Primers are complimentry nucleotides that can go on the template DNA and reform the hydrogen bond

Taq enzyme resist the excess heat and starts the production of DNA

From Dr. Yu

wikipedia

The target DNA sequence is instered into cloning vector

After insertion the vector and target DNA fregments are bound together and recombinant DNA is created

The recombinant DNA put into bacteria ,which result in production of several identicals by the process of transformation

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• DNA and mRNA are isolated from the cells

• After insertion both are simply detected

• Cell culture also grow for constant supply of cells that are ready for isolation

cell culture is al culture that is grow in artificial conditions.

In DNA isolation DNA is exttracted from cell in pure form and then separated

This happen,cell is place in tube which is filled with solution

Solution contain enzyme.chemicals and salts that break and open the cell

Enzyme helps to dissolve protein in cell Chemicals destroy all RNA

Salts put DNA out of solution by spin in centrifuge and DNA move at bottom of tube and collected from bottom

After this cycle in centrifuge solution is poured off and DNA resuspended in next solution

This result in concentrated DNA,which result in thousands of copies of each gene.

DNA ISOLATION .

• Expressed DNA(codes for protein synthesis can obtain for isolation)

• When this add to cell,cell is ruptured and cell contents exposed to synthetic beads that code with thymine nucleotides.

• Because Adenine and thymine pair together in DNA poly A tail and synthetic beads attach to one another.

• When they bind,cell components washed away without removing mRNA

Double standard DNA is produced by complimentry DNA and DNA polymerase enzyme

THIS PROJECT WAS HELD FOR DETERMINE THE SEQUENCE OF CHEMICAL BASE PAIRS THAT MAKE HUMAN DNA.ALSO IDENTIFYNG ALL GENE OF HUMAN GENOME

AMERICAN DOCTOR ALVIN TRIVELPIECE SUGGESTED THE PROJECT IN 1987

www.nobelprize.org

According to this project 20,000 to 25,000 genes identify in human

DNA

Determine the sequence of chemical base pair in human DNA

• It is technique in which information encoded in gene for the synthesis of protein molecule.

• The cell reads the sequence of the gene in group of three bases

• Eacg group of three bases corrosponding to 20 different amino acids to build the protein

1-Transcription 2-processing 3-non-coding RNA maturation 4-RNA export 5-Translation 6-protein folding

transcription is a process in which segment of DNA use to generate RNA template The DNA segment is “read” by an enzyme called RNA polymerase, which produces a strand of RNA that is complimentary to the DNA

Processing: This Priimary RNA transcript and modified and convert

mRNA that use in translation,mRNA splice to remove non-coding parts .so that only coding parts remain

Non-coding maturation: non-coding parts help in further processed.e.g.non-

protein parts transcribed as pre ribosomal RNA and after cleavage it become ribosomal RNA

Majority of RNA transported from nucleus to cytoplasm.some RNA function in nucleus,most move from nucleus to cytosol,,all the RNA include in protein synthesis

Translation: The final mRNA carries the information needed to code for

proteins.Every three base pairs on the mRNA corresponds to a binding site for a transfer RNA (tRNA) which carries an amino acid. The amino acids are then linked together in a chain by a ribosome to create a rudimentary protein chain

protein folding

- The long chain of amino acids folds to form a three-dimensional structures by using enzymes called chaperones. This three-dimensional structure is the final, functional form of the protein