Localization of Non-Histone Nuclear Proteins by Immunocytochemistry in Somatic Embryos and Pollen Grains

Nuclear proteins, in general, as molecules involved in the regulation of differential gene expression play a main role in nuclear differentiation. They can either be structural factors, required for the attachment of specific DNA or RNA molecules to the nuclear scaffold (Verheijen et al., 1988) or specific DNA or RNA binding factors with a possible role in processing, transcription and/or replication (Berezney, 1984; Busch, 1984, Holoubek, 1984). In spite of their important role they are scarcely known, especially in plant cells; for this reason we have commenced this immunocytochemical study in two experimental systems, plant somatic embryogenesis and pollen grain development, where striking nuclear activity changes occur.