Plant desiccation: polysome loss not due to ribonuclease.

During desiccation of the drought-tolerant moss Tortula ruralis polysome levels decline substantially before any increase in ribonuclease activity is observed. Furthermore, ribosomes in the desiccated moss are not complexed with messenger RNA fragments. It is concluded that ribosome runoff and failure to re-form an initiation complex mediate polysome loss during desiccation.