End-to-end chromosome attachments in mitotic interphase and their possible significance to meiotic chromosome pairing

Cytological studies on telophase and early prophase in roottip cells of several plant species (Allium cepa, 2n=16; four Crepis species, including Crepis capillaris, 2n=6; Callitriche hermaphroditica, 2n=6; Nigella arvensis, 2n=12; Secale cereale, 2n=14) revealed that chromosome ends are attached two by two forming chains of chromosomes (interphase associations). In these chains homologous chromosomes are presumably located adjacent to each other. In Crepis capillaris it was observed that the two nucleolar chromosomes form a separate ring one end attached to the ring of the four remaining chromosomes and the other end attached to the nucleolus. It is proposed that these end-to-end attachments have significance for chromosome pairing in meiosis. The adjacent location of homologous chromosomes in the interphase associations would facilitate rapid and regular synapsis.