title: Producing exposed coat-free embryos.
abstract: Production of embryos that are free of tough outer coats facilitates studies that are not possible with embryos surrounded by impenetrable envelopes. This report describes a new procedure for preventing formation of fertilisation membranes in the sea urchin (Lytechinus pictus) model. This procedure involves treating unfertilised eggs with the enzyme alpha-amylase, which cleaves alpha-1,4 glucosidic bonds in the vitelline layer. A major advantage of this method is that it is very well defined and completely controllable with alpha-amylase inhibitor. The results suggest that intact alpha-1,4 glucosidic bonds are essential for vitelline layer integrity required for formation of the fertilisation membrane. Eggs treated with alpha-amylase possessed the same surface lectin receptors as untreated eggs and, as shown by light and transmission electron microscopy, produced healthy, cleaving embryos that were free of fertilisation envelopes.
authors.affiliation: Department of Biology, California State University, Northridge 91330-8303, USA.
authors.forename: M F
authors.initials: MF
authors.lastname: Daily
authors.forename: V H
authors.initials: VH
authors.lastname: Latham
authors.forename: C M
authors.initials: CM
authors.lastname: Garcia
authors.forename: C L
authors.initials: CL
authors.lastname: Hockman
authors.forename: H
authors.initials: H
authors.lastname: Chun
authors.forename: M L
authors.initials: ML
authors.lastname: Oppenheimer
authors.forename: S P
authors.initials: SP
authors.lastname: West
authors.forename: K
authors.initials: K
authors.lastname: Rostamiany
authors.forename: R L
authors.initials: RL
authors.lastname: Chao
authors.forename: E G
authors.initials: EG
authors.lastname: Pollock
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000648:ultrastructure; D005306:Fertilization; D008854:Microscopy, Electron; D010063:Ovum / Q000648:ultrastructure*; D012617:Sea Urchins; D014817:Vitelline Membrane; D015053:Zygote / Q000648:ultrastructure*; D000516:alpha-Amylases / Q000378:metabolism
chemical_list: D000516:alpha-Amylases