FIGURE 7.

At least three nonoverlapping GW-rich regions that are different from the ortholog-conserved GW-rich region can independently bind Ago2. The dot graph on top indicates the distribution of tryptophan in GW182. W, every tryptophan (magenta diamond); WG/GW, a glycine right adjacent to tryptophan (red triangle); AW/WA, an alanine right adjacent to tryptophan (blue diamond); W only, no glycine or alanine right adjacent to tryptophan (green diamond). The majority of the tryptophans are adjacent to either a glycine or alanine. The schematic of GW182 is indicated below the dot graph. GW-rich region, box in yellow; ortholog-conserved GW-rich region (“aa1074-1144”) (Till et al. 2007), box in red. Compared with GW1Δ12, which contains the ortholog-conserved region, GW1Δ1a, GW1Δ1b, and GW1Δ5 are the three nonoverlapping regions identified in the current study that binds Ago2. The amino acid sequence alignment between GW1Δ5/GW1Δ1b and ortholog-conserved GW-rich region was performed using ExPASy website tool. *Represent sequence identity.