Figure S2. Effects of RNA interference with
lin-41 and
oma-1/2 on expression of several transcripts that selectively associate with LIN-41. Fluorescence and DIC microscopy were used to examine the expression of GFP::3xFLAG::CYB-3 (A-F; strain DG4271) SPN-4::GFP::3xFLAG (G-L; strain DG4158), and GFP::3xFLAG::MEG-1 (M-R; strain DG4213) after
lin-41(RNAi),
oma-1(RNAi;
oma-2(RNAi); or control(RNAi) treatment. Living animals were examined on the second day of adulthood. In several species, translational regulation of B-type cyclins has been observed to contribute to the regulation of meiotic maturation (reviews by Kim et al. 2013).
cyb-3 mRNA, which encodes cyclin B3, is a 6.7-fold enriched in the LIN-1 immunopurified samples (File S3). Thus, we examined expression of
cyb-3 expression pattern using GFP::3xFLAG::CYB-3 is expressed in all eugenic nuclei in the adult hermaphrodite gonad (panel B) and that
lin-41(RNAi) did not alter the GFP::3xFLAG::CYB-3 expression pattern (panel D; n=25). We also examined GFP::3xFLAG::CYB-3 expression on day 1 of adulthood in
lin-41(
n2914) (strain DG4386, n=25) and obtained similar results. Thus, misregulation of
cyb-3 expression is unlikely to contribute to the premature M-phase entry defect in
lin-41 null mutant oocytes. We did observe a slight reduction in GFP::3xFLAG::CYB-3 expression in the most proximal oocytes (-1 to -4) after
oma-1(RNAi);
oma-2(RNAi) on day 2 of adulthood (indicated by arrowheads in panel F; n=28) and in
oma-1(
zu405te33);
oma-2(
te51) null mutants on day 1 of adulthood (strain DG4390; n=60). Whether this slight reduction in CYB-3 levels contributes to (or is a consequence of) the M-phase entry defect in
oma-1;
oma-2 mutants will require further study. Surprisingly, we observed an expansion of GFP::3xFLAG::MEG-1 expression following
oma-1(RNAi);
oma-2(RNAi) treatment (panel R; n=33). This phenotype differs from that observed in the
oma-1(
zu405te33);
oma-2(
te51) double null mutant in the background in which GFP::3xFLAG::MEG-1 exhibits weak but not expanded expression (see Figure 11 and its discussion in the main text). The expression level of GFP::3xFLAG::MEG-1 appeared lower following
oma-1(RNAi);
oma-2(RNAi) as compared to that observed in the
fog-2(
oz40) and
acy-4(
ok1806) genetic backgrounds (see Figure 12, E-H). A possible explanation is that the RNAi treatment might reduce but not eliminate OMA-1/2 function. There may be sufficient residual function to enable the OMA-1/2 promotion of some MEG-1 expression. This combined with the low meiotic maturation rate might lead to the accumulation and expansion of GFP::3xFLAG::MEG-1 expression, analogous to that observed in unmated
fog-2(
oz40) females and
acy-4(
ok1806) hermaphrodites. Bars, 50 um.