Life Sciences Commons^™

Differential Effects Of Methyl Jasmonate On Growth And Division Of Etiolated Zucchini Cotyledons, E Stoynova-Bakalova, Pi Petrov, L Gigova, Ti Baskin

Biology Department Faculty Publication Series

No abstract provided.

Intercourse Between Cell Wall And Cytoplasm Exemplified By Arabinogalactan Proteins And Cortical Microtubules, A Driouich, Ti Baskin

Biology Department Faculty Publication Series

No abstract provided.

Morphological Convergence As A Consequence Of Extreme Functional Demands: Examples From The Feeding System Of Natricine Snakes, A Herrel, Se Vincent, Me Alfaro, S Van Wassenbergh, B Vanhooydonck, Dj Irschick

Biology Department Faculty Publication Series

Despite repeated acquisitions of aquatic or semi-aquatic lifestyles revolving around piscivory, snakes have not evolved suction feeding. Instead, snakes use frontally or laterally directed strikes to capture prey under water. If the aquatic medium constrains strike performance because of its physical properties, we predict morphological and functional convergence in snakes that use similar strike behaviours. Here we use natricine snakes to test for such patterns of convergence in morphology and function. Our data show that frontal strikers have converged on a similar morphology characterized by narrow elongate heads with a reduced projected frontal surface area. Moreover, simple computational fluid dynamics …

Expression Profiling Identifies Novel Hh/Gli-Regulated Genes In Developing Zebrafish Embryos, Sadie A. Bergeron, Luis A. Milla, Rosario Villegas, Meng-Chieh Shen, Shawn M. Burgess, Miguel L. Allende, Rolf O. Karlstrom, Verónica Palma

Biology Department Faculty Publication Series

The Hedgehog (Hh) signaling pathway plays critical instructional roles during embryonic development. Misregulation of Hh/Gli signaling is a major causative factor in human congenital disorders and in a variety of cancers. The zebrafish is a powerful genetic model for the study of Hh signaling during embryogenesis, as a large number of mutants that affect different components of the Hh/Gli signaling system have been identified. By performing global profiling of gene expression in different Hh/Gli gain- and loss-of-function scenarios we identified known (e.g., ptc1 and nkx2.2a) and novel Hh-regulated genes that are differentially expressed in embryos with altered Hh/Gli signaling …

Actin Depolymerizing Factor Is Essential For Viability In Plants, And Its Phosphoregulation Is Important For Tip Growth, Rc Augustine, L Vidali, Kp Kleinman, M Bezanilla

Biology Department Faculty Publication Series

No abstract provided.

Rapid Large-Scale Evolutionary Divergence In Morphology And Performance Associated With Exploitation Of A Different Dietary Resource, Anthony Herrel, Katleen Huyghe, Bieke Vanhooydonck, Thierry Backeljau, Karin Breugelmans, Irena Grbac, Raoul Van Damme, Duncan J. Irschick

Biology Department Faculty Publication Series

Although rapid adaptive changes in morphology on ecological time scales are now well documented in natural populations, the effects of such changes on whole-organism performance capacity and the consequences on ecological dynamics at the population level are often unclear. Here we show how lizards have rapidly evolved differences in head morphology, bite strength, and digestive tract structure after experimental introduction into a novel environment. Despite the short time scale (≈36 years) since this introduction, these changes in morphology and performance parallel those typically documented among species and even families of lizards in both the type and extent of their specialization. …

Tissue-Specific Requirements For Specific Domains In The Ferm Protein Moe/Epb4.1i5 During Early Zebrafish Development, Arne K. Christensen, Abbie M. Jensen

Biology Department Faculty Publication Series

Background

The FERM domain containing protein Mosaic Eyes (Moe) interacts with Crumbs proteins, which are important regulators of apical identity and size. In zebrafish, loss-of-function mutations in moe result in defects in brain ventricle formation, retinal pigmented epithelium and neural retinal development, pericardial edema, and tail curvature. In humans and mice, there are two major alternately spliced isoforms of the Moe orthologue, Erythrocyte Protein Band 4.1-Like 5 (Epb4.1l5), which we have named Epb4.1l5long and Epb4.1l5short, that differ after the FERM domain. Interestingly, Moe and both Epb4.1l5 isoforms have a putative C' terminal Type-I PDZ-Binding Domain (PBD). We previously showed that …

Two Leucine-Rich Repeat Receptor Kinases Mediate Signaling, Linking Cell Wall Biosynthesis And Acc Synthase In Arabidopsis, Sl Xu, A Rahman, Ti Baskin, Jj Kieber

Biology Department Faculty Publication Series

No abstract provided.

Geographic Diversity Cline Of R Gene Homologs In Wild Populations Of Solanum Pimpinellifolium (Solanaceae), Ana L. Caicedo

Biology Department Faculty Publication Series

Plant resistance (R) genes tend to be highly variable within plant species and are thought to be under natural selection; however, little is known about the geographic distribution of R gene diversity within and among plant populations. To determine the possible roles of demography and selection on R gene evolution, patterns of diversity at the multigenic Cf-2 R gene family were studied in Solanum pimpinellifolium populations along the northern coast of Peru. Population diversity levels of Cf-2 homologs follow a latitudinal cline, consistent with the species's history of gradual colonization of the Peruvian coast and population variation in …

Of Arcs And Vaults: The Biomechanics Of Bone-Cracking In Spotted Hyenas (Crocuta Crocuta), Jaime B. Tanner, Elizabeth R. Dumont, Sharleen T. Sakai, Barbara L. Lundrigan, Kay E. Holekamp

Biology Department Faculty Publication Series

The ability to break open large bones has evolved independently in only three groups of carnivorous mammals, all of which have robust teeth, vaulted foreheads, and pronounced sagittal crests. One unusual skull feature, present in bone-cracking members of the family Hyaenidae, is a caudally elongated frontal sinus, hypothesized to function in resistance to bending and stress dissipation during bone-cracking. In the present study, we used finite element (FE) analysis to examine patterns of stress distribution in the spotted hyena (Crocuta crocuta) skull during unilateral biting, and inquire about the functional role of the fronto-parietal sinus in stress dissipation. …

Graded Hedgehog And Fibroblast Growth Factor Signaling Independently Regulate Pituitary Cell Fates And Help Establish The Pars Distalis And Pars Intermedia Of The Zebrafish Adenohypophysis, Burcu Guner, A. Tuba Ozacar, Jeanne E. Thomas, Rolf O. Karlstrom

Biology Department Faculty Publication Series

The vertebrate adenohypophysis forms as a placode at the anterior margin of the neural plate, requiring both hedgehog (Hh) and fibroblast growth factor (Fgf) mediated cell-cell signaling for induction and survival of endocrine cell types. Using small molecule inhibitors to modulate signaling levels during zebrafish development we show that graded Hh and Fgf signaling independently help establish the two subdomains of the adenohypophysis, the anteriorly located pars distalis (PD) and the posterior pars intermedia (PI). High levels of Hh signaling are required for formation of the PD and differentiation of anterior endocrine cell types, whereas lower levels of Hh signaling …