Manduca sexta vitellogenin is a phosphoglycolipoprotein (Mᵣ ∼ 500,000) that contains two copies of the apoproteins (apovitellogenin-I, Mᵣ 180,000 and apovitellogenin-II Mᵣ 45,000), 13 percent lipids, 3 percent carbohydrates and 0.6 percent phosphorus. The two apoproteins are immunologically distinct and apovitellogenin-II is not completely accessible to the aqueous environment in the intact molecule. The carbohydrate moiety located on apovitellogenin-I has a high mannose structure (Man₉ GlcNAc₂). Follicle membranes bind ¹²⁵I-labeled vitellogenin with high affinity and specificity (K(D) ≃ 1.3 x 10⁻⁸ M). Total binding sites were estimated at 4 x 10¹⁴ sites/g of follicle membrane protein. The binding was sensitive to pH and calcium. Competition studies showed that binding of vitellogenin was blocked by vitellin and deglycosylated vitellogenin but not by lipophorin, microvitellogenin or apovitellogenin-II. These results suggest that the uptake of vitellogenin involves binding to specific receptors on follicle membranes and the carbohydrate moiety and apovitellogenin-II are not involved in the interaction with the receptors.

No description available.

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2003. / Appendix consists of reprints and manuscripts of five papers co-authored with others. Includes bibliographical references. Also partially available electronically via World Wide Web in PDF format; online version lacks appendix.

Fat body tissue was taken from female Manduca larvae throughout the fifth instar. The samples were prepared for histological study and electron microscopy. Hemolymph samples were collected and analyzed for protein profile and concentration. The data showed that the fat body underwent a series of changes with development. These include an increase in cell size, and accumulation of lipid and glycogen during the feeding phase of the instar, and the formation of protein and urate granules during the wandering stage. Also apparent was the cyclic development of a reticular system on the cell surfaces. Maximum development of the system coincided with the period of highest protein concentration in the hemolymph, while its disappearance is coincident with a drop in hemolymph protein concentration and formation of fat body granules. Thus the fat body plays a synthetic role early in the instar and becomes a storage tissue as pupation approaches.

Thesis (Ph. D.)--University of Oregon, 2005. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 118-133). Also available for download via the World Wide Web; free to University of Oregon users.

Thesis (Ph.D.)--Tufts University, 2003. / Adviser: Barry A. Trimmer. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 165-178). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Thesis (M.S.)--University of Nevada, Reno, 2006. / "August, 2006." Includes bibliographical references (leaves 112-116). Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [200x]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.

Thesis (Ph.D.)--Ohio State University, 1977. / Includes vita. Includes bibliographical references (leaves 127-140). Available online via OhioLINK's ETD Center.

Thesis (Ph. D.)--University of Oregon, 2004. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 99-113). Also available for download via the World Wide Web; free to University of Oregon users.

Thesis (M.S.)--University of Nevada, Reno, 2007. / "December, 2007." Includes bibliographical references (leaves 45-46). Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2008]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.