Cell biology of settlement and adhesion processes of biofouling algae

[摘要] The aim of the research presented in this thesis was to investigate the cell biology behind the settlement and adhesion processes of biofouling algae. Using the fluorescent dye FM 1-43 in Ulva zoospores to follow membrane recycling, rapid mass membrane retrieval of FM 1-43-labelled plasma membrane was found to occur to an endosomal compartment during settlement. Biolistic delivery of dextran Oregon Green BAPTA-1 and Texas Red enabled ratiometric imaging with a 5-fold greater response to Ca\(^{2+}\)-ionophores than AM-ester Ca\(^{2+}\) indicators. During settlement, zoospores exhibited both localised and diffuse increases in cytosolic calcium implying a role in secretion of the adhesive. Secretion of redox-active substrates was detected using amperometry when settled spores were mechano-stimulated. Secretory events were similar to those seen in bovine chromaffin cells with the presence of foot signals in the recordings implying a role for a ‘fusion pore’ in exocytosis. Using DAF-FM DA nitric oxide (NO) production in Seminavis robusta was found to be 4-fold greater on a surface to which the cells adhered weakly than on a surface to which they attached more strongly. Increased NO reduced attachment strength and it is thought that NO may play a signalling and/or regulatory role in diatom adhesion.

[发布机构] University:University of Birmingham;Department:School of Biosciences

[关键词] Q Science;QH Natural history;QH301 Biology