Gene cloning strategies

The sequence of the gene can be used to deduce the amino acid sequence of the protein encoded by the gene. The DNA and amino acid sequences can then be used to identify similar sequences in the large sequence databases such as GenBank (www.ncbi.nlm.nh.gov) or SWISSPROT (www.expasy.org). The chemical data obtained form the mutant combined with the sequence data from the gene that is defective in the mutant can then provide information on the function of the gene in the biosynthesis of a certain class of phenolic compounds. 

Several methods to clone genes will be discussed in the next three sections. The ability to clone genes was revolutionized by the development 

---

Walbot, V., 1992, Strategies for mutagenesis and gene cloning using transposon tagging and T-DNA insertional mutagenesis, Annu. Rev. Plant Physiol. Plant Mol. Biol. 43 49-82. 

Besides the abundant nodulins like Lb, GS, uricase and sucrose synthetase, many other enzymes involved in nodule metabolism are induced during the course of nodule development (see Verma Nadler, 1984). However, owing to the relatively low abundance of these enzymes and their mRNAs in nodules, none of the cognate genes have been cloned and new cloning strategies need to be employed to isolate these relatively less abundantly expressed nodulin sequences. 

An ingenious cloning strategy. In the cloning of the gene for the a chain of the T-cell receptor, T-cell cDNAs were hybridized with B-cell mRNAs. What was the purpose of this hybridization step Can the principle be applied generally ... 

---