Involvement in Meiotic Prophase of H1 Histone Kinase and p34cdc2 Homologues in Lily (Lilium longiflorum) Microsporocytes: (lily microsporocyte/p34cdc2 kinase/meiosis/pachytene)

Abstract

We have taken advantage of the synchrony of meiotic prophase I in Lilium microsporocytes to investigate the presence and involvement in four stages of meiotic prophase I (leptotene, zygotene, pachytene, and diplotene) of the p34cdc2 H1 histone kinase, a component of MPF and a key participant in division control in other eukaryotes. H1 kinase activity showed a peak pattern during meiotic prophase I with the highest kinase activity at pachytene. A monoclonal antibody directed against a highly conserved region of p34cdc2 (termed the ‘PSTAIR’) recognized three major protein forms by immunoblotting. The highest level of the fastest‐migrating form was observed at pachytene, coinciding with the highest activity of H1 kinase. Both the proteins recognized by the anti‐PSTAIR antibody and H1 histone kinase activity were retained on beads conjugated with p13suc1, a protein known to physically associate with p34cdc2. These observations suggest that p34cdc2 or protein(s) highly homologous to p34cdc2 is a component of Lilium H1 histone kinase and plays a role in regulating meiotic prophase I. Copyright © 1991, Wiley Blackwell. All rights reserved