title: Cell wall deposition during morphogenesis in fucoid algae.
abstract: Cell was deposition was investigated during morphogenesis in zygotes of Pelvetia compressa (J. Agardh) De Toni. Young zygotes are spherical and wall is deposited uniformly, but at germination (about 10 h after fertilization) wall deposition becomes localized to the apex of the tip-growing rhizoid. Wall deposition was investigated before and after the initiation of tip growth by disrupting cytoskeleton, secretion or cellulose deposition; effects on wall strength and structure were examined. All three were involved in generating wall strength in both spherical and tip-growing zygotes, but their relative importance were different at the two developmental stages. Much of the wall strength in young zygotes was dependent on F-actin, whereas cellulose and a sulfated component, probably a fucan (F2), were most important in tip growing zygotes. Some treatments had contrasting effects at the two developmental stages; for example, disruption of F-actin or inhibition of secretion weakened walls in spherical zygotes but strengthened those in tip-growing zygotes. Transmission electron microscopic analysis showed that most treatments that altered wall strength induced modifications of internal wall structure.
authors.affiliation: University of Utah, Department of Biology, 257 South 1400 East, Salt Lake City, Utah, USA. bisgrove@biology.utah.edu
authors.forename: S R
authors.initials: SR
authors.lastname: Bisgrove
authors.forename: D L
authors.initials: DL
authors.lastname: Kropf
mesh_terms: D000199:Actins / Q000378:metabolism; D020126:Brefeldin A / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D002453:Cell Cycle; D016764:Cell Polarity / Q000187:drug effects; D002473:Cell Wall / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004136:Dinitrobenzenes / Q000494:pharmacology; D005306:Fertilization; D006056:Golgi Apparatus / Q000187:drug effects; D006540:Herbicides / Q000494:pharmacology; D009024:Morphogenesis; D009997:Osmotic Pressure; D000459:Phaeophyceae / Q000166:cytology / Q000187:drug effects / Q000254:growth & development* / Q000648:ultrastructure; D011134:Polysaccharides / Q000096:biosynthesis; D012623:Seawater; D013424:Sulfanilamides; D013844:Thiazoles / Q000494:pharmacology; D053778:Thiazolidines; D015053:Zygote / Q000166:cytology / Q000254:growth & development
chemical_list: D000199:Actins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D004136:Dinitrobenzenes; D006540:Herbicides; D011134:Polysaccharides; D013424:Sulfanilamides; D013844:Thiazoles; D053778:Thiazolidines; D020126:Brefeldin A; C012465:oryzalin; D002482:Cellulose; C007789:fucoidan; C037068:latrunculin B; D004121:Dimethyl Sulfoxide