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Full-Text Articles in Life Sciences
Emma Lucy Braun's Forest Plots In Eastern North America, Robert Ricklefs
Emma Lucy Braun's Forest Plots In Eastern North America, Robert Ricklefs
Biology Department Faculty Works
No abstract provided.
Bet-Hedging In Bacteriocin Producing Escherichia Coli Populations: The Single Cell Perspective, Bihter Bayramoglu, David Toubiana, Simon Van Vliet, R. Inglis, Nadav Shnerb, Osnat Gillor
Bet-Hedging In Bacteriocin Producing Escherichia Coli Populations: The Single Cell Perspective, Bihter Bayramoglu, David Toubiana, Simon Van Vliet, R. Inglis, Nadav Shnerb, Osnat Gillor
Biology Department Faculty Works
No abstract provided.
Chronic Plasmodium Brasilianum Infections In Wild Peruvian Tamarins, Gideon Erkenswick, Mrinalini Watsa, M. Pacheco, Ananias Escalante, Patricia Parker, Georges Snounou
Chronic Plasmodium Brasilianum Infections In Wild Peruvian Tamarins, Gideon Erkenswick, Mrinalini Watsa, M. Pacheco, Ananias Escalante, Patricia Parker, Georges Snounou
Biology Department Faculty Works
There is an increased interest in potential zoonotic malarias. To date, Plasmodium malariae that infects humans remains indistinguishable from Plasmodium brasilianum, which is widespread among New World primates. Distributed throughout tropical Central and South America, the Callitrichidae are small arboreal primates in which detection of natural Plasmodium infection has been extremely rare. Most prior screening efforts have been limited to small samples, the use of low-probability detection methods, or both. Rarely have screening efforts implemented a longitudinal sampling design. Through an annual mark-recapture program of two sympatric callitrichids, the emperor (Saguinus imperator) and saddleback (Saguinus fuscicollis) tamarins, whole blood samples …
The Sulfoquinovosyltransferaselike Enzyme Sqd2.2 Is Involved In Flavonoid Glycosylation, Regulating Sugar Metabolism And Seed Setting In Rice, Xuemin Wang, Qingwen Shen, Xinqiao Zhan, Yueyun Hong
The Sulfoquinovosyltransferaselike Enzyme Sqd2.2 Is Involved In Flavonoid Glycosylation, Regulating Sugar Metabolism And Seed Setting In Rice, Xuemin Wang, Qingwen Shen, Xinqiao Zhan, Yueyun Hong
Biology Department Faculty Works
Seed setting is an important trait that contributes to seed yield and relies greatly on starchaccumulation. In this study, a sulfoquinovosyl transferase-like protein, designated as SQD2.2involved in seed setting and flavonoid accumulation, was identified and characterized in rice.Rice SQD2.2 is localized to the cytoplasm, and the SQD2.2 transcript was highest in leaves. RiceSQD2.2-overexpressing (OE) plants exhibited a decreased seed setting rate and diminished tillernumber simultaneously with an increased glycosidic flavonoid level compared with wild-type(WT) plants. SQD2.2 catalyzes the glycosylation of apigenin to produce apigenin 7-O-glucosideusing uridine diphosphate-glucose (UDPG) as a sugar donor, but it failed to compensate forsulfoquinovosyldiacylglycerol (SQDG) synthesis …
A Genetic Signature Of The Evolution Of Loss Of Flight In The Galapagos Cormorant, Patricia Parker, Alejandro Burga, Weiguang Wang, Eyal Ben-David, Paul Wolf, Andrew Ramey, Claudio Verdugo, Karen Lyons, Leonid Kruglyak
A Genetic Signature Of The Evolution Of Loss Of Flight In The Galapagos Cormorant, Patricia Parker, Alejandro Burga, Weiguang Wang, Eyal Ben-David, Paul Wolf, Andrew Ramey, Claudio Verdugo, Karen Lyons, Leonid Kruglyak
Biology Department Faculty Works
We have a limited understanding of the genetic and molecular basis of evolutionary changes in the size and proportion of limbs. We studied wing and pectoral skeleton reduction leading to flightlessness in the Galapagos cormorant (Phalacrocorax harrisi). We sequenced and de novo assembled the genomes of four cormorant species and applied a predictive and comparative genomics approach to find candidate variants that may have contributed to the evolution of flightlessness. These analyses and cross-species experiments in Caenorhabditis elegans and in chondrogenic cell lines implicated variants in genes necessary for transcriptional regulation and function of the primary cilium. Cilia are essential …
Growth Trade-Offs Accompany The Emergence Of Glycolytic Metabolism In Shewanella Oneidensis Mr-1, Lon Chubiz, Christopher Marx
Growth Trade-Offs Accompany The Emergence Of Glycolytic Metabolism In Shewanella Oneidensis Mr-1, Lon Chubiz, Christopher Marx
Biology Department Faculty Works
Bacteria increase their metabolic capacity via the acquisition of genetic material or by the mutation of genes already present in the genome. Here, we explore the mechanisms and trade-offs involved when Shewanella oneidensis, a bacterium that typically consumes small organic and amino acids, rapidly evolves to expand its metabolic capacity to catabolize glucose after a short period of adaptation to a glucose-rich environment. Using whole-genome sequencing and genetic approaches, we discovered that deletions in a region including the transcriptional repressor (nagR) that regulates the expression of genes associated with catabolism of N-acetylglucosamine are the common basis for evolved glucose metabolism …
Identification Of The Potentiating Mutations And Synergistic Epistasis That Enabled The Evolution Of Inter-Species Cooperation, Sarah Douglas, Lon Chubiz, William Harcombe, Christopher Marx
Identification Of The Potentiating Mutations And Synergistic Epistasis That Enabled The Evolution Of Inter-Species Cooperation, Sarah Douglas, Lon Chubiz, William Harcombe, Christopher Marx
Biology Department Faculty Works
Microbes often engage in cooperation through releasing biosynthetic compounds required by other species to grow. Given that production of costly biosynthetic metabolites is generally subjected to multiple layers of negative feedback, single mutations may frequently be insufficient to generate cooperative phenotypes. Synergistic epistatic interactions between multiple coordinated changes may thus often underlie the evolution of cooperation through overproduction of metabolites. To test the importance of synergistic mutations in cooperation we used an engineered bacterial consortium of an Escherichia coli methionine auxotroph and Salmonella enterica. S. enterica relies on carbon by-products from E. coli if lactose is the only carbon source. …
From Galapagos Doves To Passerines: Spillover Of Haemoproteus Multipigmentatus, Maricruz Jaramillo, Sage Rohrer, Patricia Parker
From Galapagos Doves To Passerines: Spillover Of Haemoproteus Multipigmentatus, Maricruz Jaramillo, Sage Rohrer, Patricia Parker
Biology Department Faculty Works
Haemoproteus (Haemoproteus) multipigmentatus, a haemosporidian parasite thought to be specific to columbiform birds, was detected in passeriform birds on Santiago Island in the Galapagos archipelago. We surveyed birds along an altitudinal gradient on the islands of Santa Cruz, Isabela and Santiago between June 2013 and July 2015. Molecular screening of 2254 individuals from 25 species of endemic and introduced birds revealed clusters of passerine birds positive for H. multipigmentatus on Santiago Island that coincide with captures of Galapagos doves at sampled sites. Of 507 individuals from 10 species of endemic passerines sampled on Santiago, 58 individuals from 6 species were …
Evolution Of Floral Zygomorphy In Androecium And Corolla In Solanaceae, Jingbo Zhang, Peter Stevens, Wenheng Zhang
Evolution Of Floral Zygomorphy In Androecium And Corolla In Solanaceae, Jingbo Zhang, Peter Stevens, Wenheng Zhang
Biology Department Faculty Works
In Solanaceae, a group dominated by actinomorphic‐flowered species, floral zygomorphy is frequently observed among the early‐branching clades. Morphological studies indicated that a zygomorphic androecium is much more common than a zygomorphic corolla in the family. Ontogenic studies suggested the evolution of floral zygomorphy in these two whorls is independent. Here, we have examined the evolution of floral symmetry in the androecium and corolla in Solanaceae. The character states of floral symmetry were assembled for androecium and corolla separately, and ancestral state reconstructions were carried out at both the genus and species levels for Solanaceae and its outgroups. Correlation tests were …
Phylogenetic Patterns Of Rarity In A Regional Species Pool Of Tropical Woody Plants, M. Loza, Iván Jiménez, Peter Jørgensen, Gabriel Arellano, Manuel Macía, Vania Torrez, Robert Ricklefs
Phylogenetic Patterns Of Rarity In A Regional Species Pool Of Tropical Woody Plants, M. Loza, Iván Jiménez, Peter Jørgensen, Gabriel Arellano, Manuel Macía, Vania Torrez, Robert Ricklefs
Biology Department Faculty Works
AimRarity, which is believed to influence extinction risk, can be defined in terms of local abundance, geographical range size and habitat breadth. Phylogenetic patterns in these attributes provide insight into the extent to which rarity and extinction risk are conserved during evolution and the potential for species‐level heritability. We evaluated phylogenetic signal (i.e., related species resembling each other more than species drawn at random) and evolutionary conservatism (similarity among related species exceeding that expected from a Brownian model of evolution) in three axes of rarity (local abundance, geographical range size and habitat breadth) among species in a regional pool of …
Temporal And Demographic Blood Parasite Dynamics In Two Free-Ranging Neotropical Primates, Gideon Erkenswick, Mrinalini Watsa, Alfonso Gozalo, Nicole Dmytryk, Patricia Parker
Temporal And Demographic Blood Parasite Dynamics In Two Free-Ranging Neotropical Primates, Gideon Erkenswick, Mrinalini Watsa, Alfonso Gozalo, Nicole Dmytryk, Patricia Parker
Biology Department Faculty Works
Parasite-host relationships are influenced by several factors intrinsic to hosts, such as social standing, group membership, sex, and age. However, in wild populations, temporal variation in parasite distributions and concomitant infections can alter these patterns. We used microscropy and molecular methods to screen for naturally occurring haemoparasitic infections in two Neotropical primate host populations, the saddleback (Leontocebus weddelli) and emperor (Saguinus imperator) tamarin, in the lowland tropical rainforests of southeastern Peru. Repeat sampling was conducted from known individuals over a three-year period to test for parasite-host and parasite-parasite associations. Three parasites were detected in L. weddelli including Trypanosoma minasense, Mansonella …
Host Sympatry And Body Size Influence Parasite Straggling Rate In A Highly Connected Multihost, Multiparasite System, Jose Rivera-Parra, Iris Levin, Kevin Johnson, Patricia Parker
Host Sympatry And Body Size Influence Parasite Straggling Rate In A Highly Connected Multihost, Multiparasite System, Jose Rivera-Parra, Iris Levin, Kevin Johnson, Patricia Parker
Biology Department Faculty Works
Parasite lineages commonly diverge when host lineages diverge. However, when large clades of hosts and parasites are analyzed, some cases suggest host switching as another major diversification mechanism. The first step in host switching is the appearance of a parasite on an atypical host, or “straggling.” We analyze the conditions associated with straggling events. We use five species of colonially nesting seabirds from the Galapagos Archipelago and two genera of highly specific ectoparasitic lice to examine host switching. We use both genetic and morphological identification of lice, together with measurements of spatial distribution of hosts in mixed breeding colonies, to …
Phospholipase Dζ Enhances Diacylglycerol Flux Into Triacylglycerol, Wenyu Yang, Geliang Wang, Jia Li, Philip Bates, Xuemin Wang, Douglas Allen
Phospholipase Dζ Enhances Diacylglycerol Flux Into Triacylglycerol, Wenyu Yang, Geliang Wang, Jia Li, Philip Bates, Xuemin Wang, Douglas Allen
Biology Department Faculty Works
Plant seeds are the primary source of triacylglycerols (TAG) for food, feed, fuel, and industrial applications. As TAG is produced from diacylglycerol (DAG), successful engineering strategies to enhance TAG levels have focused on the conversion of DAG to TAG. However, the production of TAG can be limited by flux through the enzymatic reactions that supply DAG. In this study, two Arabidopsis phospholipase Dζ genes (AtPLDζ1 and AtPLDζ2) were coexpressed in Camelina sativa to test whether the conversion of phosphatidylcholine to DAG impacts TAG levels in seeds. The resulting transgenic plants produced 2% to 3% more TAG as a component of …
Passerine Morphology: External Measurements Of Approximately One-Quarter Of Passerine Bird Species, Robert Ricklefs
Passerine Morphology: External Measurements Of Approximately One-Quarter Of Passerine Bird Species, Robert Ricklefs
Biology Department Faculty Works
Studies of community organization and clade diversification that include functional traits have become an important component of the analysis of ecological and evolved systems. Such studies frequently are limited by availability of consistently collected data. Here, I present a data set including eight measurements of the external morphology of 1642 species, roughly one‐quarter of all passerine birds (Aves: Order Passeriformes), from all parts of the world, characterizing the relative proportions of the wing, tail, legs, and beak. Specimens were measured opportunistically over the past 40 years in museums in the United States and Europe. Numbers of individuals measured per species …
Seed Dispersal For The Unusual Inflated Berries Of Burmeistera (Campanulaceae), Diana Gamba, N. Maguiña, Camilo Calderón-Acevedo, Karina Torres, Nathan Muchhala
Seed Dispersal For The Unusual Inflated Berries Of Burmeistera (Campanulaceae), Diana Gamba, N. Maguiña, Camilo Calderón-Acevedo, Karina Torres, Nathan Muchhala
Biology Department Faculty Works
Examining dispersal is critical for understanding the diversity of Andean-centered plant lineages, like Burmeistera (Campanulaceae). One-third of its species present an unusual inflated berry. Unlike the bright colors of non-inflated fruits in the genus, these fruits are typically dull-green; however, the fact that the seeds are loosely held in the placenta and easily removed when touched seems to suggest adaptation to animal dispersal. We studied two inflated-baccate species, Burmeistera glabrata and B. borjensis, with the aim of testing the non-exclusive hypotheses that their seeds are dispersed by (1) small mammals, (2) slugs, or (3) adult flies that develop inside the …