The Csm1-Interaction Domain of Dsn1 is required for the first meiotic nuclear division.

<p>A) Dyads produced by <i>spo11Δ spo12Δ</i>, <i>mam1Δ spo11Δ spo12Δ</i>, <i>P_GPD1-DSN1 spo11Δ spo12Δ P_GPD1-dsn1-Δ110 spo11Δ spo12Δ</i> strains and <i>spo11Δ spo12Δ P_CLB2-DSN1</i> cells transformed with either pRS306-<i>DSN1</i> or pRS306-<i>DSN1-Box2A</i> or pRS306-<i>DSN1-Box3A</i> or pRS306-<i>DSN1-Δ75</i> or pRS306-<i>DSN1-Δ110</i> were dissected on YPD plates and grown at 30°C. Spore viability (n = 100) was scored after 3 days. B) Detection of homozygous <i>URA3-</i>GFP and DNA in tetrads produced by <i>P_GPD1-DSN1 and P_GPD1-dsn1-Δ110 cells</i>. Tetrads produced by the strains were dissected onto YPD plates and grown at 30°C. Spore viability (n = 100) was scored after 3 days. C–E) Immunofluorescence analysis. <i>P_GPD1-DSN1</i> and <i>P_GPD1-dsn1-Δ110</i> cells containing Pds1-myc18, Rec8-ha3 and heterozygous <i>URA3</i>-GFP were fixed and analysed by fluorescence microscopy. C) Nuclear division, and the percentage of cells containing Pds1, Rec8, metaphase I spindles and separated sister <i>URA3-</i>GFP dots were scored in <i>P_GPD1-DSN1</i> and <i>P_GPD1-dsn1-Δ110</i> cells. D) Images showing various stages of meiosis in wild type and mutant cells following fixation and fluorescence microscopy to detect <i>URA3</i>-GFP, tubulin, DNA and Pds1-myc18. E) Percentage of anaphase I cells (Pds1 negative and one bipolar spindle) with divided or undivided nuclei. Data (panels C–E) are of a single representative experiment of at least three independent repeats.