Fig 2: H2A.Z levels are elevated in neuronal progenitors that are deficient for Elp1. (A–G) E11.5. (A,D) PAX3 expression in dorsal pole DRG progenitors. (B,E) H2A.Z expression in the DRG. (C,F) PAX3/H2A.Z overlay. (G) Quantification of corrected total cell fluorescence (CTCF) shows that H2A.Z levels are elevated in PAX3+ cells in the DRG of Elp1 CKOs (P=0.004). (H–L) E17.5. (H) ELP1 levels are diminished in the brains of Wnt1-Cre; Elp1LoxP/LoxP CKO embryos. Residual ELP1 protein present in the CKO lanes is likely due to the presence of tissue outside of the Wnt1-Cre activity domain. (I) H2A.Z levels are consistently elevated in the brains of Wnt1-Cre; Elp1LoxP/LoxP CKO embryos. (J) Average, normalized signal intensity=1.86 for the control and 4.06 for the CKO (P-value=0.04, n=3 control and 4 CKO). (K,L) Although H2A.Z levels are elevated in the absence of Elp1, the levels of acetylated H2A.Z are normal, resulting in a reduced ratio of acetylated to total H2A.Z in the CKO. (M) Adult Pax6-Cre; Elp1LoxP/LoxP CKO mice exhibit elevated levels of H2A.Z in the retina. Average, normalized signal intensity in pooled samples=0.51 in the control and 0.91 in the CKO. The faint band migrating slightly above the H2A.Z band in I and K corresponds to the ubiquitinated form of H2A.Z (Lamaa et al., 2020). (N) Quantitative RTPCR shows that H2a.z transcript levels may be slightly elevated in Elp1 CKO embryos, but the difference is not significant (P=0.21, n=3 control and 3 CKO). Error bars denote SEM; scale bar: 20 µm. C, control; CKO, conditional knockout; DRG DP, dorsal root ganglion dorsal pole; CTCF, corrected total cell fluorescence.

Fig 3: Localization of histones H2AX and H2A.Z in the spermatozoa of O. oratoria. (a) Localization of DNA and H2AX by immunofluorescence. Merged, images of DNA and H2AX or bright field and H2AX. (b) Ultrastructural localization of histone H2AX (blue arrow) in spermatozoa by 10 nm colloidal gold. (c) Immunofluorescent localization of DNA and H2A.Z. merged, images of DNA and H2A.Z or bright field (DIC) and H2A.Z. (d) Ultrastructural localization of histone H2A.Z (red arrow) in spermatozoa by 10 nm colloidal gold. Gold particles show the location of histones H2AX and H2A.Z in the nucleus (Ba and Da) and the granular material (bb and Db). DNA was stained by DAPI. DIC: Bright field. The scale bars indicate 5 µm (a, c) and 500 nm (b, d)