We have discussed and/or demonstrated the following: 1. Many enzymes and structural proteins have been identified as meiosis-specific proteins. These can be classified according to their metabolic behavior. 2. We obtained and analyzed 18 cDNA clones from lily meiocytes. One of them, LIM15, was similar to known genes like RecA, RAD57, and DMC1/ISC2, and might function in pairing and recombination. 3. Transcription of these genes is regulated by their regulator region(s). When such a regulator, mei2 promoter sequence isolated from S. pombe, was ligated with the proper vector and transfected, it functioned specifically in meiotic cells but not in the somatic cells tested. 4. Presence of a new lamin, lamin B3 was identified in mammalian spermatocytes and the transfection of lamin B3 gene (inserted into vector) into somatic cells alters the nuclear shape, possibly expressing a characteristic shape of meiotic nuclei. Lamin B3 was synthesized after meiosis-specific processing of lamin B2 mRNA. Other protein specific to meiotic nuclear-skeleton (MNS1) were found and characterized. All these events were studied basically focussing on homologous pairing and recombination which take place in meiosis I. We recognize the necessity of further studies on these and other events like the structure and segregation of chromosomes and the suppression of somatic gene expression during meiosis.