Show simple item record

Files in this item


Item metadata

dc.contributor.advisorTucker, John Barry
dc.contributor.authorOckleford, Colin Douglas
dc.coverage.spatial1 vol.en_US
dc.description.abstractLong lengths of microtubules apparently break down very rapidly (100mum in under a second) during a hitherto undescribed feeding response. Microtubular axopodia elastically resist mild bending along their longitudinal axes. They yield non-elastically when more severe bending is applied; bends are formed at certain points along their longitudinal axes. A polarised repair process returns bent axopodia to their normal straight form. Bends under repair move out along axopodia towards their tips. Employing these bends as markers it has been shown that breakdown of microtubules takes place at the tips of tubules at the distal ends of axopodia when axopodial shortening is induced with colchicine. Evidence has been gained which suggests that microtubule growth and breakdown may be restricted to precisely localised areas within an organism. Apart from this crude control over the presence or absence of tubules in a certain position, it appeal's that the cell has provision for the re-deployment of prefabricated groups of microtubules. A study of tubule regrowth and of the formation of patterned aggregates of microtubules after experimental disassembly suggests that tubule initiation, orientation and pattern formation occur as temporally separate processes. Pattern formation does not appear to depend on a pre-existing pattern of nucleating sites based on a two-dimensional template.en_US
dc.publisherUniversity of St Andrews
dc.titleThe properties and development of axopodial microtubules in the heliozoan Actinophrys Solen_US
dc.type.qualificationnamePhD Doctor of Philosophyen_US
dc.publisher.institutionThe University of St Andrewsen_US

This item appears in the following Collection(s)

Show simple item record