ORIGINAL ARTICLE

PCR Based Detection of Insulin Like Protein from Dolichos lablab L.

In the current research work, the genetic region corresponding to both alpha and beta chains of insulin like protein from Dolichos lablab L was identified using PCR. Earlier study by Venâncio et al., (2003) has revealed that the amino acid sequence of alpha and beta chains of bovine insulin has significant similarity to amino acid sequence of insulin like protein from legume Vigna unguiculata (cowpea). Although the amino acid sequence was available for V. unguiculata, the corresponding DNA sequence was not available in the database. Considering the resemblance in protein sequence, primers were designed using nucleotide sequences of alpha and beta chains of bovine insulin and were used for amplification of these chains from V. unguiculata and D. lablab. Genomic DNA extraction was carried out by the conventional ethanol precipitation method followed by purification using preparative AGE. Standardization on PCR amplification of alpha and Beta chain of Insulin from D. lablab L. and V. unguiculata was carried out. Results obtained for the PCR amplification of alpha and beta chains were validated by the re-amplification of gene, where the previously obtained PCR product was used as template DNA. All the above experiments suggest that the DNA sequence of both chains of insulin gene is probably highly conserved amongst different organisms as the primer designed using bovine insulin DNA sequence could amplify the same gene in plants like V. unguiculata and D. lablab L.