Uncoordinate synthesis of histone H1 in cells arrested in the G1 phase

摘要: Abstract It has been known for several years that DNA replication and histone synthesis occur concomitantly in cultured mammalian cells. Normally all five classes of histones are synthesized coordinately. However, mouse myeloma cells, synchronized by starvation isoleucine, synthesize increased amounts H1 relative to the four nucleosomal core histones. This unscheduled is reduced within 1 h after refeeding not a normal component G1. The increases coordinately again with other during S phase. inhibitors, cytosine arabinoside hydroxyurea, block S-phase levels mRNA, mRNAs, isoeleucine-starved cells decreases rapidly isoleucine. incorporation at least partially due low isoleucine content H1. Starvation lysine resulted decrease Again ratio was altered on amino acid. 3T3 starved serum also incorporated only into chromatin. different proteins changed. 0 protein predominant G These data indicate metabolism independent when cell growth arrested.