MEL-28 ^ELYS is essential for interkinetic envelope integrity and membrane recruitment. (A) Representative time-lapse images centered on chromosomes of oocytes (n = 8) expressing mCherry::H2B (magenta) and GFP::MEL-28^ELYS (green) during meiosis I and II. Timings indicated at the bottom left corners of images are from anaphase I onset. Scale bar, 5 μm. (B) Representative time-lapse images centered on chromosomes of oocytes expressing mCherry::H2B (magenta) and GFP::TBA-2^α-tubulin (green) and mCherry::HIS-11^H2B (green) during anaphase I and interkinesis in the indicated conditions. Timings indicated at the bottom left corners of images are from anaphase I onset. Scale bar, 5 μm (C) Left: Three-dimensional reconstructions centered on chromosomes of a control oocyte (top) and a MEL-28^ELYS–depleted oocyte (bottom) viewed from two different angles. Scale bar, 1 µm. Right: Two-dimensional single sections of ROIs centered on each chromosomal set. Chromosomes in magenta, membranes in contact with chromosomes in green, and plasma membrane in gray. Scale bar, 1 µm. The same control oocyte is displayed in Fig. 4 F. (D) Left: Two-dimensional single sections of ROI centered on each chromosomal set of a control oocyte (top) and a MEL-28^ELYS–depleted oocyte (bottom). Scale bar, 1 µm. Right: Three-dimensional reconstructions centered on chromosomes viewed from two different angles. Scale bar, 1 µm. Chromosomes in magenta, membranes in contact with chromosomes in green, membranes distant from chromosomes in orange, vesicles in yellow, mitochondria in purple, endoplasmic reticulum in blue, and plasma membrane in gray. Scale bar, 1 µm. (E) Top: Representative time-lapse images centered on chromosomes of oocytes expressing mCherry::H2B (magenta) and GFP::LEM-2^LEMD2/3 (green) during interkinesis and interphase in the indicated conditions. Timings indicated at the bottom left corners of images are from anaphase I onset. Scale bar, 5 μm. Bottom: Quantification of the normalized GFP::LEM-2^LEMD2/3 integrated intensity over time from anaphase I onset to interphase for the MII chromosomal set. Control in dark blue, mel-28(RNAi) in purple, mel-28(RNAi) treated with 100 ng/μl nocodazole in brown. Error bars correspond to the standard error of the mean. The orange box indicates interkinesis. Mann–Whitney test on the mean value of GFP::LEM-2^LEMD2/3 intensity in interkinesis (****P < 0.0001). (F) Quantifications of the maximal mean value of GFP::LEM-2^LEMD2/3 intensity in interkinesis normalized over background in the indicated conditions. One-way ANOVA test (****P < 0.0001, *P < 0,05).