RIP followed the methods of Peritz et al. (2006), Ji & Tulin (2016) and Mandal & Kazazian (2016).  Approximately 100 ovaries were homogenized on ice in 200 uL polysome lysis buffer.  Lysates were centrifuged and supernatants were collected. To pre-clear the lysates, they were incubated for 60 minutes at 4C with washed protein G beads.  A 20 uL sample was kept as the input control.  The final volume of remaining lysate was brought to 500 uL with lysis buffer and then divided into two tubes.  Anti-HA rat IgG1 (clone 3F10; Roche) was added to one tube and Normal Rat IgG (Sigma-Aldrich) was added to the other tube and they were incubated overnight at 4C.  For immunoprecipitation of RNPs, washed Protein G agarose beads were added to the antibody-rich lysates and mixed for 2 hours at 4C.  Beads were washed 3 times, then RNP-antibody complexes were eluted in 50 uL of elution buffer with incubation for 20 minutesat 50C. RNA was extracted using Trizol (Thermo Fisher) and purified using RNA Clean and Concentrator Kits (Zymo Research).  RNA was sent to The Centre for Applied Genomics (Toronto, Canada) for library construction and sequencing.  Stranded libraries were made with 100 ng of RNA and Illumina Stranded Total RNA Prep with Ribo-Zero Plus kits, then paired-end sequenced at 150 bases/read in one NovaSeq S4 flowcell.  The R2 file has the forward strand read.