FIGURE 8.

Replacement of Met⁸²³ in wild type RetGC1 dimerization domain with Arg inhibits binding of GCAP1 and GCAP2 but not of RD3. mOrangeRetGC1 (1 μg of DNA) was co-transfected in HEK293 cells with 0.01 μg of GCAP1-GFP (A), GCAP2-GFP (B), or RD3-GFP (C) DNA constructs as described under “Experimental Procedures”. The respective PCC values (mean ± S.E.) were as follows: for co-localization of GCAP1 with RetGC1 harboring M823R, M823E, and M823S substitutions, 0.55 ± 0.03, n = 31; 0.52 ± 0.03, n = 32; and 0.89 ± 0.01, n = 41; for GCAP2 co-localization with M823R and M823S RetGC1, 0.40 ± 0.03, n = 28 and 0.89 ± 0.01, n = 41; for RD3 co-localization with M823R RetGC1, 0.91 ± 0.01, n = 44 (see Table 1 for the summary of the quantitative analysis).