TRANSIENT EXPRESSION OF GUS AND THE 2S-ALBUMIN GENE FROM BRAZIL-NUT IN PEANUT (ARACHIS-HYPOGAEA L) SEED EXPLANTS USING PARTICLE BOMBARDMENT

The effect of parameters involved in the transformation efficiency of peanut (Arachis hypogaea L.) seed tissues by direct gene transfer usin g a helium inflow particle bombardment device was evaluated. Transient gene expression was affected by both particle and DNA amounts, and wa s positively correlated with gene copy number, as determined by P-gluc uronidase (GUS) activity assays. No influence of plasmid size on GUS g ene expression was observed. Transcriptional control of GUS by either the CaMV 35S or the 2S promoter from Brazil nut 2S albumin gene varied with the developmental stage of the seed and was approximately tenfol d greater under the influence of the 35S promoter than under the 2S pr omoter. The gene products of both the Brazil nut methionine-rich 2S al bumin and GUS genes under the transcriptional control of the 35S promo ter were detected by ELISA assays.