|Morris, John - Brad|
Submitted to: Alfalfa Improvement Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 4/15/2004
Publication Date: 7/18/2004
Citation: Tolford, S., Mcarthur, J.G., Morris, J.B. 2004. Lectin quantified among lablab purpureus genetic resources regenerated in georgia, USA. North American Alfalfa Improvement Conference & the Trifolium Conference [abstract]. Available: www.naaic.org/meetings/national/2004naaic&tc/2004abstracts/jmorris.pdf. Interpretive Summary: Labab purpureus originates from countries worldwide and is used for forage and food in underdeveloped nations. Small acreages are grown in California and Texas. More than 90 accessions are conserved at the USDA, ARS, Plant Genetic Resources Conservation Unit, Griffin, GA. Lablab purpureus contains potential bioactive phytochemicals in sufficient quantity to be utilized in the pharmaceutical markets. The lectin FRIL, which was discovered in Phaseolus vulgaris, is present in significant quantities in the seeds of Lablab purpureus. Lectins are known to play a role in plant defenses against pathogen attack and have been reported to interact with specific glycoproteins on human cells and induce various biologic responses. FRIL has been observed to interact with the FLT3 receptor on human stem cells and prevent them from proliferating or undergoing apoptosis. We report 7 fold variability in the quantity of FRIL among 22 Lablab purpureus accessions. Genotypes with high quantities of FRIL have the potential to be utilized in the natural product or phytopharmaceutical industries.
Technical Abstract: The lectin FRIL was extracted and assayed from 22 older Lablab purpureus accessions originating from 13 different countries stored at -18 degrees C at the USDA, ARS, Plant Genetic Resources Conservation Unit, Griffin, GA, and from freshly grown Lablab purpureus genotypes produced in the field at the University of California, San Diego, CA. FRIL was isolated using sugar based affinity beads and then quantified and examined by SDS-PAGE. FRIL from Lablab purpureus demonstrates a 5-band pattern on SDS-PAGE. This heterogeneity results from the use of 2 alternate N-termini and 2 alternative glycosylation sites on the alpha chain. We found more than a 7-fold variability in the quantity of FRIL among Lablab purpureus accessions. Fresh and older Lablab purpureus seeds were consistent in terms of high FRIL producers and low FRIL producers. We also observed a large amount of heterogeneity in the relative size and coloration of the seeds suggesting that sufficient time and distance separates the beans to allow a certain amount of genetic drift. Genotypes with high FRIL indicate their potential to be utilized by the natural product or phytopharmaceutical industries as a new medicine.