Sv 40

Simian vacuolating virus 40 or Simian virus 40

1. Introduction to Animal Biotechnology MCE-404 Simian Virus 40 Submitted by:- Yashasvi Kumar Singh B .Tech Biotechnology 5 th semester 13BTBIOT062 Submitted to:- Dr. Amit Alaxander Charan Assistant Professor Department of MCE

2. Contents Serial no. Particulars Slide no. 1.) Introduction 3 2.) SV 40 vector 4 & 5 3.) Structure 6 & 7 4.) Advantages 8 5.) Future prospects 9

3. Introduction Vectors are molecular vehicles which have a direction of transfer and are used b y researchers for the transfer of foreign molecule into another host cell. A cloning vector is a small piece of DNA into which a foreign DNA fragment can be inserted. The insertion of the fragment into the cloning vector is carried out by treating the vehicle and the foreign DNA with the same restriction enzyme, then ligating the fragments together. There are many types of cloning vectors. Genetically engineered plasmids and bacteriophages (such as phage λ) are perhaps most commonly used for this purpose .

4. SV40 is for Simian vacuolating virus 40 or Simian virus 40, a polyomavirus found in both monkeys and humans. It was named for the effect it produced on infected green monkey cells, which developed unusual number of vacuoles. Like other polyomaviruses, SV40 is a DNA virus that has the potential to cause tumors. SV40 was first identified by Ben Sweet & Maurice Hilleman in 1960 when they found that between 10-30% of polio vaccines in USA were contaminated with SV-40. The complete viral genome was sequenced by Walter Fiers and his team. SV 40 Vector

5. SV40 is a spherical virus with a circular, double stranded 5,243 bp chromosomes, which incodes 5 proteins, viz., small-t, large-t (both early protein), VP1, VP2 and VP3 (VP= virion protein),has an origin of replication(about 80 bp) and is complexed with histones to form chromatin. Large-T is essential for viral replication, while VP1, VP2 and VP3 form the viral capsid. In laboratory, it is multiplied in cultured kidney cells of African green monkey; infected cells lyse after 4 days releasing upto 10 raise to the power 5 virions/cell. SV40 plasmids (vectors) can be packaged only if their DNA is within the range of 3900 to 5300 bp. SV40 is capable of multiplicity reactivation (MR). MR is the process by which two, or more, virus genomes containing otherwise lethal damage interact within an infected cell to form a viable virus genome.

6. Structure

7. Retrovirus Vectors : Retroviruses have single-stranded RNA genome. Each virus has 2 copies of genome, which resemble eukaryotic mRNAs . The viral genome reverse transcribed by reverse transcriptase into a DNA double strand copy inside the host cells. The following properties of the retroviruses are useful in their use as vectors: 1.A wide host range (Birds ,mammals and other animals) 2.Infected cells are not killed and they continue to produce virus particles over indefinite period. 3. Presence of strong promoters. Regulation of promoter action in case of some viruses. Retroviral vectors are constructed from cloned DNA genomes of retroviruses. These have the following features: 1.The vector has the viral sequences for replication, gene expression and packaging 2. DNA inserts may either replace or be located in the non essential coding regions of the viral genome. 3.The viral proteins are usually provided by the helper virus or a provirus. 4.DNA copies of the retrovirus genome are used as vectors ,generally as shuttle vectors.

8. Advantages of using SV 40 as a vector :- SV40 vectors (SV40) are good candidates for gene transfer, as they display some unique features. SV40 is a well-known virus, nonreplicative vectors are easy-to-make. They also efficiently transduce both, resting and dividing cells, deliver persistent transgene expression to a wide range of cell types, and are nonimmunogenic. (i) it is easily modified to be nonreplicative. (ii) it can be produced in large quantities. (iii) it infects almost every cell type that has been tested, both dividing and quiescent. (iv) it is not immunogenic it allows long-term expression of the transgene. (vi) its molecular biology is well studied. (vii) the effects in humans of wild-type SV40 have been documented.

9. Future Prospects Many ongoing research have been going on to develop recombinant SV 40 v ectors. It serves as a potential for new vectors. Because of it , retro viruses can be understood in more detail . Wide range of selection for gene transfer experiments .

10. Bibliography www.google.com www.wikipedia.org http://www.ncbi.nlm.nih.gov www.oxfordjournals.org http://www.jbc.org