Extended Data Fig. 3: Meiotic regulators Pi and Mi exhibit asymmetry in localization in early zygotes.
From: Gamete fusion triggers bipartite transcription factor assembly to block re-fertilization
a, Time-lapse showing mating of heterothallic cells expressing nuclear marker Uch2–mCherry (magenta) with the M cell co-expressing sfGFP-tagged endogenous Mi. Note the cytosolic Mi–sfGFP signal in M cells that rapidly accumulates in the P nucleus after partner fusion. The punctate signal at cell cortex in the green channel is background—probably mitochondrial—fluorescence. b, N-terminally sfGFP-tagged endogenous Pi exhibits a weak nuclear staining in P cells during mating in homothallic cells co-expressing nuclear marker Uch2–mCherry (magenta). Arrows point to nuclear sfGFP–Pi signal in the P cell (middle panel) and the zygote (bottom panel). c, Time-lapse showing homothallic, fusion-defective fus1Δ cells co-expressing N-terminally sfGFP-tagged endogenous Pi and nuclear marker Uch2–mCherry. Arrows point to Pi nuclear accumulation. d, Time-lapse showing transient fusion between pak2Δ cells expressing NLS–sfGFP–SynZip4 and mCherry–SynZip3. Note the accumulation of both fluorophores in the M nucleus and minimal transfer of the green fluorophore into the P cell that eventually sporulates (arrows) e, Left panel follows the mating of wild-type cells expressing cytosolic sfGFP–SynZip4 and mCherry–SynZip3. Right panel quantifies both fluorescent signals in the central region of the two cells corresponding to the two nuclei, as labelled on the scheme, and is presented as in Fig. 3e.
