http://hdl.handle.net/10057/388 Search the Channel s http://soar.wichita.edu:8080/dspace/simple-search http://hdl.handle.net/10057/2285 title: Analysis of differential glycosylation patterns of human FSH authors: Chambers, Carrie; Shuai, Bin; Bousfield, George <br>abstract: Follicle stimulating hormone (FSH) is a glycoprotein hormone with two subunits, a and ß, and is required for gamete development. Our data suggest that estrogen is responsible for inhibiting the glycosylation of FSHß in reproductive-age women, thus producing a di-glycosylated FSH with higher biological activity than the tetra-glycosylated form. The difference in glycosylation of two subunits is suspected to be due to activity of different oligosaccharyltransferase(OST) isoforms. OSTs are responsible for the first step in N-glycosylation. Factors including signal peptide hydrophobicity of a and ß maybe contribute to selective usage of OST, and hence modulate N-glycosylation. Therefore our hypothesis is that N-glycosylation of FSH subunits is regulated by the differential interactions between OST isoforms and the signal peptides of each subunit, and the differential interaction is modulated by hormones such as estrogen. To test our hypothesis, we will genetically engineer chimeric hFSH subunits by swapping the signal peptide sequences of a and ß. Constructs with the chimeric sequences will be introduced into immortalized gonadotrope cell lines. FSH glycoforms expressed in the cell lines will be examined using Western Blot. If our hypothesis is correct, then we would expect to detect unglycosylated a subunit in the transfected cell lines. Different hormones such as estrogen will be used to treat the cell lines and the difference in FSH subunit glycosylation will be examined <br>description: Paper presented to the 5th Annual Symposium on Graduate Research and Scholarly Projects (GRASP) held at the Hughes Metropolitan Complex, Wichita State University, May 1, 2009. <br> Thu, 30 Apr 2009 22:58:59 GMT http://hdl.handle.net/10057/1392 title: Expression of a novel follicle-stimulating hormone glycoform relating to fertility authors: Tran, T.; Bousfield, George R.; Shuai, B. <br>abstract: LH) and follicle-stimulating hormone (FSH), play significant roles in follicular development and maintenance of the estrous cycle. FSH specifically functions to stimulate follicle growth, estrogen synthesis and serve as a selection factor for dominant follicles, which are essential to maintain fertility. FSH exists in two glycoforms: diglycosylated FSH (DiGlycFSH) and tetraglycosylated FSH (TetGlycFSH). The DiGlycFSH contains carbohydrates on the α subunit only, while TetGlycFSH has carbohydrates on both α and β subunits. Pituitary extraction of FSH shows that in young reproductive age women, the DiGlycFSH is more abundant than TetGlycFSH, whereas post menopausal women have more pituitary TetGlycFSH. Bioassay of DiGlycFSH shows that it has greater biological activity than TetGlycFSH. Due to limited availability of DiGlycFSH, bacterial expression of recombinant human (h)FSH (rec hFSH) is needed to provide sufficient glycoform for structural and biological studies. We report our efforts towards synthesis of DiGlycFSH, which involves expression of rec hFSHβ, separation, purification from soluble and insoluble fractions, folding, and reassociation with human chorionic gonadotropin (hCGα). Protein function will be characterized by receptor binding and steroidogenesis assays. <br>description: Paper presented to the 4th Annual Symposium on Graduate Research and Scholarly Projects (GRASP) held at the Hughes Metropolitan Complex, Wichita State University, April 25, 2008. <br> Thu, 24 Apr 2008 22:58:59 GMT http://hdl.handle.net/10057/1382 title: Causes of variation in damage by folivores: the roles of ecosystem productivity and habitat complexity authors: Shrestha, S.; Russell, Leland <br>abstract: Understanding the causes of variation in herbivore damage to plants is very important in that crop loss can be reduced, and damage may be manipulated to limit population growth of invasive weed species. My research focuses on variation of damage by insects to leaf tissues of tall thistle (Cirsium altissimum) rosettes under differing levels of ecosystem productivity and habitat complexity. I address four specific questions in my research. First, does ecosystem productivity affect the amount of tissue loss to insect herbivory? Second, does habitat complexity, in terms of litter and local species richness, affect tissue loss to insect herbivory? Third, is there any interaction effect between ecosystem productivity and habitat complexity on plant tissue loss to insect herbivores? Fourth, do ecosystem productivity and habitat complexity affect the fresh biomass of insect carnivores and herbivores? At each of two sites four 40 m X 40 m plots were established for ecosystem productivity manipulations and subplots within the 40 m X 40 m plots are used for manipulations of habitat complexity. Nitrogen was added to experimentally increase ecosystem productivity and litter (dead plant parts that are lying down) and plant species richness were manipulated for habitat complexity. Preliminary results from the first year of field work showed that the mean (± standard error) proportions of leaves damaged severely (>50% leaf area damaged) in control plots were 0.06 ± 0.01 in May, 0.25±0.01 in August and 0.10±0.07 in October. In nitrogen addition plots mean proportions of leaves damaged severely were 0.04±0.01 in May, 0.22±0.04 in August and 0.06±0.01 in October. Although nitrogen addition increased plant standing crop by 16.7%, differences in proportion of leaves damaged severely between control and N-addition plots were not statistically significant at any of the three months. Statistical analysis of these data is on-going. <br>description: Paper presented to the 4th Annual Symposium on Graduate Research and Scholarly Projects (GRASP) held at the Hughes Metropolitan Complex, Wichita State University, April 25, 2008. <br> Thu, 24 Apr 2008 22:58:59 GMT http://hdl.handle.net/10057/802 title: Expression of growth differentiation factor-9 in the developing ovary and in nonovarian tissues authors: Bowser, Jessica Lynn; Hendry, William J.; Srikanthan, Sowmya; May, Jeffrey V. <br>description: Paper presented to the 2nd Annual Symposium on Graduate Research and Scholarly Projects (GRASP) held at the Rhatigan Student Center, Wichita State University, April 28, 2006. Research completed at the Department of Biological Sciences, Wichita State University. <br> Thu, 27 Apr 2006 22:58:59 GMT