Skip to main content
. 2018 Apr 23;45(2):212–225.e7. doi: 10.1016/j.devcel.2018.03.018

Figure 5.

Figure 5

Mutants Expressing Non-phosphorylatable LMN-1 Display Aberrant Recombination Intermediates and Elevated Germline Apoptosis, Concomitant with an Occasional Delay in Meiotic Progression and Pairing

(A) Schematic representation of a C. elegans gonad, showing all meiotic stages in spatial and temporal order. Gonads were divided into seven zones of equal size for describing the behavior of markers along the time course of prophase I. See Figure S5 for additional data.

(B) Percentage of nuclei with a given number of RAD-51 foci (indicative of meiotic DNA DSB induction and repair kinetics) in the wild-type and non-phosphorylatable lmn-1 mutant. [gfp::lmn-1], n = 3 gonads; [gfp::lmn-1S8A], n = 3 gonads.

(C) X chromosome pairing kinetics, as indicated by percentages of nuclei containing paired or unpaired signals for the X chromosomal pairing center protein, HIM-8, in wild-type and [gfp::lmn-1S8A] gonads. [gfp::lmn-1], n = 5 gonads; [gfp::lmn-1S8A], n = 4 gonads. p values were calculated using the chi-square test: p = 0.5726 (ns), 0.3149 (ns), ∗∗∗∗p < 0.001, p = 0.6538 (ns), p = 0.4578 (ns), ∗p = 0.0448, and ∗p = 0.0247 for each germline zone, respectively.

(D) Percentage of the meiotic region with SUN-1Ser8pi staining, indicating ongoing recombination and SC formation. [gfp::lmn-1], n = 12 gonads; [gfp::lmn-1S8A], n = 17 gonads. p = 0.3179 (ns). Scatter plots indicate mean and SD.

(E) Quantification of SYTO-12-positive apoptotic corpses per gonad arm. [gfp::lmn-1], n = 61 gonads; [gfp::lmn-1S8A], n = 77 gonads. ∗∗∗p = 0.0002, calculated using the Mann-Whitney U test. Scatter plots indicate mean and SD.

(F) Representative images of diakinesis oocytes expressing either wild-type or non-phosphorylatable LMN-1 in an apoptosis-proficient background and in the ced-3(n717) apoptosis mutant. The arrowhead indicates aberrantly joined DAPI-positive structures. Scale bars, 5 μm.

(G) Quantification of DAPI-stained bodies in -1 and -2 diakinesis oocytes in the presence or absence of germline apoptosis (ced-3) and deficient for DNA DSBs (spo-11(ok79)). [gfp::lmn-1], n = 50 oocytes; [gfp::lmn-1S32,403A], n = 83 oocytes; [gfp::lmn-1S8A], n = 78 oocytes. In the ced-3 mutant background: [gfp::lmn-1], n = 94 oocytes; [gfp::lmn-1S32,403A], n = 101 oocytes; [gfp::lmn-1S8A], n = 118 oocytes. In the spo-11 mutant background: [gfp::lmn-1], n = 58 oocytes; [gfp::lmn-1S8A], n = 63 oocytes.