FIGURE 2:

Ric-8 regulates the function of Cta within the Fog signaling pathway. (A) Expression of Ric-8-GFP, but not GFP alone, rescues the ability of cells depleted of endogenous Ric-8 to respond to Fog. Scale bar, 20 μm. (B) The number of GFP or Ric-8-GFP–transfected cells within a population depleted of endogenous Ric-8 was scored for their ability to contract in response to Fog (±SEM). (C) Cells depleted of endogenous Ric-8 or Cta were transfected with constitutively active Cta (Cta_QL), RhoGEF2-GFP, or Ric-8-GFP + Fog treatment. Their ability to drive constriction was quantified as a percentage of the number of cells contracting within the population (±SEM). (D) Summary chart illustrating the epistatic relationship of Ric-8 in the Fog pathway. Transfected DNA and targeted dsRNA are indicated. +, ≥15% of transfected cells within a population constricted; –, ≤15% of transfected cells within a population constricted. (E) Cells were treated with control or Ric-8 dsRNA and transfected with a dual-expression construct for both Cta (WT, constitutively inactive:GA, or constitutively active:QL) and mCherry under separate promoters. Immunoblotting revealed equal amounts of Cta in control and Ric-8 dsRNA–treated cells; anti-dsRed was used as a protein loading control, and anti-Ric-8 to verify protein depletion.