Pollen grain , due to its unique structural organization , an extremely convenient experimental model both cytological , molecular and genetic factors. Ease of their isolation , extraction of pollen and DNA, RNA and proteins had resulted in male gametophyte cells of angiosperms are currently among the most intensively studied plant structures . Extremely intense in recent years the development of research tools exploring the genome resulted in numerous works on various aspects of gene expression during microsporogenesis and microgametogenesis in angiosperms .

Meiosis is a process which have a great weight for development and continuity of life on Earth. In a great majority of organisms the cells which are made during meiosis are directly involved in sex reproduction processes. High development of molecular biology techniques makes possible an identifica- tion of numerous genes involved in meiotic division. Model organisms in these research in the first place are yeasts and Caenorhabditis elegans. The last years bring also many informations about genetic and molecular regulation of meiosis in plants, mainly in Arabidopsis thaliana.

Cajal bodies ( called Cajal bodies, CBs ) was first described 100 years ago in mammalian neurons . It is now known that CB are highly conserved structures present in the somatic and germ cells of plants and animals. CB marker protein coilin , a phosphoprotein probably responsible for location of numerous macromolecules in Cajal bodies . The presence of small nuclear RNA ( snRNA ) in the CB indicates the participation of this structure in the spatial organization of the elements involved in the submission of pre- mRNA splicing .