DNA Barcoding, Cantu, Eddie
College of Science and Mathematics
DNA barcoding is a tool utilized for species identification. It involves the sequencing of a standard region of DNA from the genome of individual species, this sequences are then stored in a database called GenBank. Once in the sequences are stored in GenBank they can be retrieved for comparison and identification of genus and species. In order to identify a land plant species the DNA barcode must be retrievable with a single pair of primers and provide maximal discrimination among species. The perfect candidate for this in land plants was the long chain of the enzyme ribulose-1,5-bisphosphate carboxylase / oxygenase (RuBisCO) which is involved in photosynthesis with the gene found in the chloroplasts DNA with the name of rbcL.
Since the gene that has been chosen is present in the chloroplast DNA then this technique can be performed on a single leaf from a land plant. One leaf from a land plant was collected in the morning and taken into lab for experimentation the same day. The leaf was collected at this coordinates N29.692549, W95.53997. DNA kit was used in order to isolate rbcl for DNA barcoding. 10-20 mg (1/4 inch) of leaf tissue was collected and treated with lysis solution for extraction of DNA (rbcL). For purifying of the solution a proteins precipitation solution was utilized. After the DNA was extracted polymerase chain reaction (PCR) was performed with the addition of a set of primers specific for rbcL. Following PCR a confirmation was done via Gel Electrophoresis and UV blue light observation.
The identification protocol yielded the genus and species of the land plant to be Gelsemium elegans (yellow jasmine).
