Full Text Linkhttpswwwncbinlmnihgovpubmed824647 TitleHozumi

Full Text Link:https://www.ncbi.nlm.nih.gov/pubmed/824647 Title:Hozumi &Tonegawa paper “Evidence for Somatic Rearrangement of Immunoglobulin Genes Coding for Variable and Constant Regions”

Questions:

1. Discuss the experimental design of the study. Explain how it tests the hypothesis put forth by the authors.
2. Discuss Figure 2. How was it obtained? What does it show?

Solution

Experimental design is divided into three parts:

1. BamH1 digestion

2.agarose gel electrophoresis

3.hybridisation

As according to author,the hypothesis was that somatic rearrangement of immunoglobin genes of v (variable) and c (constant) region took place.

They have prooved this hypothesis,by looking over change in BamH1 site in myeoma cells as compare to embryo cells.As fidrst we have eluted DNA from myeloma cells and from embryo cell.then we have cut them with BamH1 enzyme and look over the pattern of gel , run in electrophoresis.THen the autor eluted different size bands. and hybridised with the n terminal fragment of v chains and c terminal fragment of constant chain.

size differences show that both v and c chain combined and form recombinant chain which showed by difference in sizes.

2. figure 2 depict migration and molecular weight both,author want to prove that in control embryo cell line there is two peak was there by using whole mrna probe at migration:5cm as well as 12cm mgration molecular weight 6 and 3.9 milllion respectively ,

where as by using one probe of gettin peak a 3\'half,we got peak at 6 million molecular weight only.

But on the contrary in tumor cell line there is only one peak byusing whole mrna probe and 3\' half probe,which show that there is combination or recombination take place.