Molecule Genetic

Molecule Genetic

MOLECULE GENETIC SUMMARY 4

MoleculeGenetic Summary

Inthe Lee &amp Nurse (1987) article, the authors inspected thecomplementation used in cloning a human homologue of the fissionyeast cell cycle control gene cdc2. The authors hypothesized that thehuman CDC2 gene has been sequenced, and it well encodes a protein ofthe same molecular load as S.pombecdc2having a 63% uniqueness of amino-acid residues. This functional aswell as structural similarity implies that elements of cell cycleorganization are likely to be conserved amid yeast and humans, whichcan probably be identified in all eukaryotic cells (Lee &amp Nurse,1987).

Thequestion here was whether there are some human CDC2 gene cancomplement a mutation in the cdc2 gene. In establishing this, theauthors used complementation of mutants in detecting genes havingsimilar functions. The human cDNA library was employed in selecting agene which could complement a defective cdc2 function. During theprocess, the S.pombetemperature susceptible mutant strain cdc2-33 leul-32 becameco-transformed with plasmid vector pDB262 and the human cDNA libraryin the Okayama as well as Berg expression vector. A sum of 106leucine prototrophic transformants became grown for 24 hours attolerant temperature of 29 degrees celcius and were then transferredto a restrictive temperature of 36 degrees celcius. Fivetransformants were indicated to form colonies. 2-4 library plasmidswere recovered into E. coli from each of the initial fivetransformants. Two plasmids, pOB231 and pOB245, isolated from twovaried initial yeast transformants, were indicated to complementcdc2-33 mutation. Restriction mapping showed that the plasmids wereidentical and each contained a similar 2-kilobase (kb) insert (Lee &ampNurse, 1987).

Throughthe yeast experiment, the authors were in a position to demonstrateand support the idea that the human CDC2Hs gene can provide all thefunctions of cdc2Sp in fission yeast (Lee &amp Nurse, 1987).However, it is important for the authors to do a next experiment thatwould establish whether CDC2Hs performs a similar role as cdc2Sp inthe control of human cell cycle.

References

Lee,G.M. &amp Nurse, P. (1987). Complementation used to clone a humanhomologue of the fission yeast cell cycle control gene cdc2. Nature,Vol. 327 pp 31-35.