Figure 3. ego-1 Interacts Genetically with him-17.

Each panel shows one hermaphrodite gonad arm at 24 hr post-L4 stage. Asterisk indicates distal end of each arm. TZ, “transition zone” containing germ cells in early meiotic prophase (leptotene-zygotene stages). ego-1 and him-17 null alleles are shown (see Supplemental Experimental Procedures). Animals were raised at 20°C.

(A) The wild-type germline includes distal mitotic cells, meiotic cells, and oocytes in diakinesis stage of meiosis. Sperm are present at the proximal end (although most are out of the plane of focus).

(B) Organization of the him-17 germline is normal.

(C) Overall organization of the ego-1 germline is normal, although some nuclei are enlarged, the leptotene-zygotene region is expanded, and oocytes are small.

(D) The ego-1;him-17 germline is small and lacks oocytes. Sperm nuclei are irregular in size (inset).