Chromatin Abnormalities in Dmrt7 Mutant Diplotene Germ Cells
(A and B) MSCI occurs normally in mid-pachytene spermatocyte of Dmrt7 mutant. Arrows indicate XY body in all panels. Cot-1 RNA FISH (red) reveals normal silencing of sex chromosome transcription in XY body. This is consistent with wild-type mid-pachynema as described previously [16].
(C and D) HP1β localization in mid-pachytene spermatocytes. HP1β localizes to X chromosome centromere (arrowhead) in wild-type (C) and mutant (D).
(E and F) Cot-1 hybridization in diplotene. Presumptive XY body, based on DAPI and γH2AX localization, is indicated by arrow in (F).
(G and H) HP1β in diplotene. Wild-type cell (E) has HP1β throughout XY body, whereas mutant cell (H) only has localization to X chromosome centromere (arrowhead).
(I and J) H3-2meK9 localization in diplotene cells. Mutant cell (J) lacks strong concentration of this mark to the XY body seen in wild-type (I).
(K and L) H3-3meK9 localization in diplotene cells. Mutant cell (L) has no localization of this mark to the XY body. γH2AX localizes to autosomes in mutant cell, possibly indicating onset of apoptosis.
(M) Example of mutant diplotene cell with normal HP1β accumulation to the XY body.
All images except those in (M) are single Z sections.