121. Itoh, T. and R. M. Brown, Jr. 1988.
Development of cellulose synthesis in Boergesenia and Valonia.
The development of linear cellulose synthesizing
complexes (= TCs) of two selected siphonocladalean algae, Boergesenia
forbesii and Valonia ventricosa was investigated by
following the time course of the regeneration of cell walls with
the freeze fracture technique after aplanospore induction. The
following structural changes of TC development were examined:
(1) TCs initiate de novo; (2) the first nucleation of TC subunits
occurs within 2 hr in Boergesenia and 5 hr in Valonia
after aplanospore induction, immediately followed by the assembly
of cellulose microfibrils; (3) TCs increase their length during
the assembly of randomly oriented microfibrils; and, (4) TCs stop
increasing in length after the assembly of ordered microfibrils
begins, with some time lag. The data demonstrate that linear
TCs are not artificial products but dynamic entities which are
involved in the assembly of cellulose microfibrils.