Characterization of protein and transcript levels of the chaperonin containing tailless complex protein-1 and tubulin during light-regulated growth of oat seedlings.

In grass seedlings the network of cortical microtubules is reorganized during light-dependent growth of coleoptiles and mesocotyls. We investigated the effects of light-dependent growth on the relative steady-state levels of the mRNAs and protein levels of alpha-tubulin and the epsilon-subunit of the chaperonin containing tailless complex protein-1 in oat (Avena sativa) coleoptiles, which were grown in different light conditions to establish different growth responses. The soluble pools of the epsilon-subunit of the chaperonin containing tailless complex protein-1 and alpha-tubulin decreased in nonelongating coleoptiles, suggesting that the dynamics of the light-regulated soluble pool reflect the processes occurring during reorganization of cortical microtubules. The shifts in pool sizes are discussed in relation to the machinery that controls the dynamic structure of cortical microtubules in plant cells.