Fig. 6.

NsdD is required for heterokaryon formation as assessed by HAMF. Strains of opposite mating types that express fluorescent protein-tagged histone 2A variants were cocultivated to spot mycelial compartments that contained labeled nuclei of either type and, in the case of heterokaryon formation, both kinds. When derivatives of the wild-type strains D141 and Af293 were coincubated, hyphae with both fluorescently labeled nuclei could be identified (AfS81 × AfS82; white arrowheads), whereas exclusively uniform hyphae were detected when a labeled nsdDΔ strain was crossed to the Af293 descendant.