21/5/2007 - THAT IS BACTERIOPHAGE

21/5/2007 - CLONING DNA IN BACTERIOPHAGE

21/5/2007 - CONSTRUCTION OF A RECOMBINANT DNA MOLECULE

21/5/2007 - Molecular Approach For Recombination of DNA

21/5/2007 - Clonning

Clonning

–         Dolly has been clone taken from her mother’s udder.

–         Unfertilized egg cell with nucleus removed were fused with the cell from the udder

–         Fused cell was stimulated to divide and implanted into a surrogate mother.

–         Polly

•          Single diploid cell originating from adult sheep was altered (human gene coding for blood cloting factor was introduced) and the cell was fused with denucleated egg cell. The fused cell was stimulated to divide and implated into surrogate mother.

•          Lamb contains the human gene in every cell of her body.

•          Gene Therapy for severe combined immunodeficiency (SCID)

•          Gene therapy succeeded for 15 French baby boys who suffered from SCID, called X-linked SCID, because it is caused by a mutated gene encoding a subunit — called γc (gamma-c) — of the receptor for several interleukins, including interleukin-7 (IL-7).

•          IL-7 is essential for converting blood stem cells into the precursors of T cells. Boys with X-linked SCID do not develop ********al immune response system.

•          Doctors isolated blood stem cells from the bone marrow of each boy;

     treated the cells with a vector containing the normal gene for the γc interleukin receptor subunit; returned the treated cells to each donor.

•          The results: Now after as long as three and one-half years, these boys  are able to live normal lives at home instead of inside a sterile "bubble"; have normal (with two exceptions*) numbers of T cells .

21/5/2007 - Bacteriophage

Bacteriophage

Bacteriophages are bacteria viruses.

 When they infect their host they use host machinery to replicate their DNA.

 In bacteriophage vectors part of the phage DNA is replaced by the gene of interest (max. size is 15-25 kbp)

 When this new recombinant phage DNA infects a host the gene of interest will be replicated.

commonly used phage vectors include M13 and λ.

Infection of bacterial cell:

Tail sticks to the cell wall

DNA from head is squired into bacteria

Phage genes are transcribed by bacterial RNA polymerase

Corresponding mRNA is translated using bacterial machinery

Newly replicated phage DNA and head and tail protein ensemble spontaneously

Lyses of host bacteria results in formation of plagues.

•          l phage – most common vector for construct of genomic DNA

•          Cosmid vector – can accumulate up to 45 kb

–         a cross between a plasmid and l vector

–          contains antibiotic resistance genes and Ori for replication in bacteria

–         Contains cos sites to be packed in phage particles

–         Inside of bacteria, the cosmid DNA circularizes and replicates as a large plasmid

•          YAG yeast artificial chromosome ,  up to 200 to 500 kb

–         Large DNA fragments are inserted into yeast DNA sequence and introduced into yeast cell by transformation          

9/5/2007 - DNA STRUCTURE

9/5/2007 - MUON NEUTRINO

9/5/2007 - NEUTRINO DETECTION

9/5/2007 - DISCOVERY OF NEUTRINOS