Development of the germline in <i>gei-8(ok1671)</i> mutants and additional phenotypic changes induced by RNAi targeted against Y9C9A.16 (<i>sqrd-2</i>) in homozygous <i>gei-8(ok1671)</i> mutants.

<p>(<b>A</b>) The reproductive structures of a wild-type larva at the L4 stage is shown. The vulva is indicated by an arrowhead and formation of the uterus is visible next to vulval structures. The position of the lead migrating cell for the gonad (distal tip cell) during the larval L4 stage is indicated by arrow. (<b>B</b>) Development of the gonad in a young adult N2 animal. The distal gonad arm continues in growth beyond the position of the vulva (marked by arrowhead) and makes contact with the proximal gonad arm (arrow). (<b>C</b>) <i>gei-8(ok1671)</i> mutant gonadogenesis by Nomarski optics. The arrested gonad arm in a position similar to wild type L4 larva is indicated by arrow. The vulva is marked by an arrowhead. (<b>D</b>) A <i>gei-8(ok1671)</i> mutant with arrested growth of the gonad as visualized by DAPI staining. The distal tip of arrested gonad is marked by an arrow and the vulva by an arrowhead. (<b>E</b>, <b>F</b>, <b>G</b>, <b>H</b>, <b>I</b> and <b>J</b>) Additional phenotypic changes induced by RNAi targeted against Y9C9A.16 (<i>sqrd-2</i>) region including three 21U-RNAs: 21ur-2020, 21ur-11733 and 21ur-9201 in <i>gei-8(ok1671)</i> homozygous mutant animals. (<b>E</b>) A <i>gei-8(ok1671)</i> mutant treated with <i>sqrd-2</i> RNAi shows growth of the gonad beyond the usual arrest point, reaching the position of the vulva (marked by arrow and arrowhead, respectively). (<b>F</b>) Additional phenotypes of <i>gei-8(ok1671)</i> animals treated with <i>sqrd-2</i> RNAi. Nomarski optics view of homozygous <i>gei-8(ok1671)</i> larva treated with <i>sqrd-2</i> RNAi revealing frequent growth defects, including irregular body shapes, (distention of proximal part of the body and thin elongation of the distal part of the body) and extended growth of the distal part of the gonad. The gonad is visualized by DAPI staining in panel <b>G</b> (distal arm of the gonad is marked by right arrow, proximal arm of the gonad is marked by left arrow). Arrowhead indicates the position of vulva in panels E, F and G. (<b>H</b>) Additional growth defects induced by <i>sqrd-2</i> RNAi in homozygous <i>gei-8(ok1671)</i> worms including a Pvul phenotype (arrowhead), accumulation of gonadal cells with a possible incomplete second vulva formation (left arrow) and a distal arm of germline that fails to turn and instead continues to grow in the direction of the thin and elongated tail (right arrow). (<b>I</b>) A mutant animal with germline growth directional changes of both gonad arms induced by <i>sqrd-2</i> RNAi: anterior gonad arm makes an incomplete turn dorsally and continues to grow in the anterior direction (left arrow) while the posterior gonad arm fails to turn and continues in additional growth towards the tail (right arrow). The position of vulva is indicated by arrowhead. (<b>J</b>) A homozygous <i>gei-8(ok1671)</i> mutant developing a convoluted irregular accumulation of cells of distal gonad arm in the position of gonad turn (marked by arrows). The position of vulva is indicated by arrowhead. Scale <b>A</b>, <b>B</b>, <b>D</b>, <b>E</b> and <b>J</b> 50 µm, <b>C</b>, <b>F</b>, <b>G</b>, <b>H</b> an <b>I</b> 100 µm.