During C. elegans hermaphrodite development, germ cells complete multiple events to become sperm or oocytes. These events include mitotic proliferation, a switch from mitosis to meiosis, progression through meiotic prophase, meiotic arrest and the meiotic divisions, as well as sex determination and gametogenesis. By analogy, additional steps in germ-line development may also fall under somatic control. We have used laser ablation to investigate the role of other somatic gonad components during hermaphrodite germ-line development with an emphasis on lineages leading to the ten somatic sheath cells that surround the germ in each arm. During L2 ,all somatic cells, except the DTCs, move to the center of the gonad forming the somatic primordium.
Arms have the usual U-shape and the gonad basement membrane is intact so that no contents leak.
Further, there is no evidence of alterations in other lineages to replace the missing cells. Miniature arms are not seen following ablation of one SS cell, ablations of combinations of dorsal and ventral uterine cells, AC ablation, or ablation of germ cells. Conclusions From these ablations, we conclude that SS cells or their descendants are promoting germ cell proliferation.