Fig. 9: P190 is conserved in PIX RhoGEF domains and required for PIX-1 function at muscle cell boundaries.

a PFAM alignment of RhoGEF domain sequences of PIX proteins from 10 species showing that P190 is absolutely conserved. In contrast, R212 is not conserved, which might explain why pix-1(gk713465) [R212Q] has no obvious phenotype. b Confocal microscopy of wild type and pix-1(gk893650) [P190S] mutant co-stained with antibodies to ATN-1 (α-actinin) and UNC-95 (top two rows), and co-stained with UNC-89 (obscurin) and PAT-6 (α-parvin) (bottom two rows). Note that in pix-1(gk893650), at the muscle cell boundary, the two halves of the zipper are separated, whereas in wild type they are together. c Confocal imaging of pix-1(gk893650) [P190S] stained with antibodies to UNC-52 (perlecan), PAT-3(β-integrin) or UNC-112 (kindlin). Note that these IAC proteins also show reduced or disrupted localization at muscle cell boundaries. Arrowheads bracket a muscle cell boundary. Each image is a representative image obtained from at least 2 fixation and immunostaining experiments, and imaging at least three different animals of each strain. Scale bar, 10 μm.