Fig. 1. ATX-2 forms a complex with a poly(A)-binding protein, and is required for the proper size of the gonad and the onset of oogenesis. (A) A wild-type gonad arm stained with DAPI. Boxed area in A includes sperm (arrow) in the spermatheca. Asterisks in all figures indicate the distal tip of a gonad arm. (B) High magnification of boxed region in A showing the small, highly condensed sperm nuclei (arrowheads). (C) atx-2(RNAi) gonad stained with DAPI; note that the proximal gonad contains only sperm. (D) An enlarged view of some sperm nuclei (arrowheads) from the gonad shown in C. (E) Same gonad as in C stained with mAb1CB4 to visualize spermatocytes and spermatids. (F) Western blot of extracts from wild-type worms (lane 1) and transgenic worms (lane 2) carrying a triple-myc-tagged allele of atx-2 (atx-2::3xmyc); the blot was probed with anti-ATX-2 mAbP1G12. (G) Western blot of extracts from wild-type worms exposed to bacterially expressed atx-2 dsRNA (lane 2) or empty vector control (lane 1). (H,I) Wild-type gonad (H, inset) and atx-2(RNAi) gonad (I) stained for ATX-2; arrows indicate non-gonadal tissues present in the preparation. (J) Left panel: a silver stained SDS-PAGE gel of ATX-2 immunoprecipitates prepared from wild-type worm extracts with either anti-ATX-2 antibodies (mAbP1G12 in lane 1; mAbP6D2 in lane 2) or anti-MEX-5 antibody (lane 3, negative control). (J) Right panel: ATX-2 immunoprecipitates from extracts of wild-type (lane 4) or atx-2(RNAi) worms (lane 5) prepared with anti-ATX-2 mAbP1G12; there is preferential depletion of the lower ATX-2 band. The immunoglobulin heavy and light chains are indicated by asterisks. (K) High-magnification light micrograph of the vulva and gonad of a pab-1(RNAi) animal. The vulva (arrowhead) is protruding from the body, and the entire gonad consists of only a few cells (asterisks mark both distal ends of the gonad). Scale bars: 50 µm.