Construction of cDNA representational difference analysis based on two cDNA libraries and identification of garlic inducible expression genes in human gastric cancer cells

Figure 1 Schematic diagram of cDNA RDA based on cDNA libraries, illustrating the subtractive hybridization and amplification steps following the representation stage and preparation of amplicons. Gray boxes (24-mer, 12-mer) represent R (or J, N)-Bam adapters

Figure 2 Morphological changes of human gastric cancer cell line BGC823 after Allitridi treatment. A: The parental cells (used as control); B: Neurite-like structures outgrew from the cell bodies and formed interconnections after exposure to 25 mg•L⁻¹ Allitridi for 96 h (5 × 40).

Figure 3 Insert sequences released from randomly selected clones (Lanes 1-12) of parental cell (BGC823) cDNA library (A) and Allitridi-treated cell (Alli823) cDNA library (B) by digestion with EcoR I and Xho I. λPhage/Hind III size marker was indicated in Lane M.

Figure 4 Agarose gel electrophoresis of difference products obtained after the first, second and third round hybridizations. BamH I-digested library DNA extracted from Alli823 and BGC823 cDNA libraries respectively (Lanes 2, 3); Amplicons of cDNA population prepared from Allitridi-treated and parental groups (used as tester and driver respectively) (Lane 4, 5); First, second and third difference products respectively (Lanes 6, 7, 8); 1 kb size marker (Lane 1) and PUC18/Hae III DNA size marker (Lane 9).

Figure 5 Northern blot analysis of FRαgene and calcyclin gene expression in BGC823 cells. FRα mRNA (A) and calcyclin mRNA (B) level was elevated after exposure to 25 mg•L⁻¹ Allitridi for 72 h.