[i] Capture probes containing 25-mer oligonucleotides were chosen from 19 Arabidopsis genes as shown in the table and coupled with different color-coded microspheres. NTSR is a sequence with 25-mer oligonucleotides chosen from the human genome that is absent in theArabidopsis genome and serves as negative control in these experiments. The complementary sequences to the capture probes of the 20 genes were synthesized with biotin tagged on the 5′-end and used as targets in the assay. The target oligonucleotides were mixed at various amounts in four tubes as indicated in the table and measured in the multiplexed assays as shown in Figure 1. In the experiment of hexaplexed assay, only the first six targets from the table were added, the results are presented in Figure 1A. In the experiment of dodecaplexed assay, all twenty targets were added and the corresponding signal of each gene was measured (Fig. 1B).