Life Sciences Commons^™

Notes On Patagium Morphology In The Gliding Flat-Tailed House Gecko (Hemidactylus Platyurus), Amber M. Petty, Tony Gamble, Aaron H. Griffing

Biological Sciences Faculty Research and Publications

Several species of geckos have independently evolved patagia, membranous features that facilitate gliding. Detailed morphological investigations of gecko patagia have largely been limited to gliding members of the genus Gekko (formerly in the genus Ptychozoon). Herein we describe the morphology of gliding patagia of the Flat-tailed House Gecko (Hemidactylus platyurus), a species with an independent evolutionary origin of gliding patagia from Gekko and an important species for researching gliding biomechanics. We compared morphology of H. platyurus with a closely related non-gliding species, the Common House Gecko (Hemidactylus frenatus). Using external examination and histological techniques, we …

Synthesis And Evaluation Of 1,3-Disubstituted Imidazolidine-2,4,5-Triones As Inhibitors Of Pyruvate Carboxylase, Nicholas O. Schneider, Keandra Gilreath, Niel M. Henriksen, William A. Donaldson, Subhabrata Chaudhury, Martin St. Maurice

Biological Sciences Faculty Research and Publications

Substituted imidazolidinetriones (IZTs) have been identified as potent inhibitors of pyruvate carboxylase (PC) through an in silico screening approach. Alkyl 2-(2,4,5-trioxo-3-substituted imidazolidin-1-yl)acetates (6i–6r) are the most potent of the series, with IC50 values between 3 and 12 μM, and several IZTs demonstrate high passive permeability across an artificial membrane. IZTs are mixed-type inhibitors with respect to pyruvate and noncompetitive with respect to ATP. This class of inhibitors appears to be selective for PC. Inhibitors in the IZT series do not inhibit the metalloenzymes human carbonic anhydrase II and matrix metalloprotease-12, and they do not inhibit the related biotin-dependent enzyme, guanidine …

Importance Of Conserved Hydrophobic Pocket Region In Yeast Mitoribosomal Ml44 Protein For Mitotranslation And Transcript Preference, Jodie M. Box, Margo E. Higgins, Rosemary A. Stuart

Biological Sciences Faculty Research and Publications

The mitochondrial ribosome (mitoribosome) is responsible for the synthesis of key oxidative phosphorylation subunits encoded by the mitochondrial genome. Defects in mitoribosomal function therefore can have serious consequences for the bioenergetic capacity of the cell. Mutation of the conserved mitoribosomal mL44 protein has been directly linked to childhood cardiomyopathy and progressive neurophysiology issues. To further explore the functional significance of the mL44 protein in supporting mitochondrial protein synthesis, we have performed a mutagenesis study of the yeast mL44 homolog, the MrpL3/mL44 protein. We specifically investigated the conserved hydrophobic pocket region of the MrpL3/mL44 protein, where the known disease-related residue …

The Food And Habitat Effects Of Detrital Kelp As A Trophic Subsidy To Seagrass-Inhabiting Mesograzers, Jessica Billinghurst

Theses: Doctorates and Masters

Seascapes are connected through the transfer of energy from the movement of fauna, detritus, and nutrients among habitats. This exchange of resources can influence food web dynamics in the recipient system, increasing productivity and biodiversity, thus creating spatial subsidies. Spatial subsidies are usually characterised by the transfer of resources from highly productive donor systems to lower productive recipient systems. However, recent work suggests that recipient systems with comparably high productivity, such as seagrass meadows, may benefit from spatial subsidies. Kelp is regularly eroded from reefs and provides a vector for nutrient and detrital transfer to seagrass meadows, where it can …

Spatial And Temporal Variation In Population Genetic Diversity In Seagrasses And The Implications For Resilience, Anna Maria Frouws

Theses: Doctorates and Masters

Seagrass ecosystems are highly productive and fulfil vital roles in the coastal environment as ecosystem engineers and keystone species. Unfortunately, anthropogenic pressures have resulted in a significant loss of seagrass habitat and associated ecosystem services. The complex and unpredictable nature of these pressures, and their increasing extent and intensity globally, makes resilience-based ecosystem management a valuable approach. Resilience-based management requires knowledge on processes enhancing ecosystem resilience and on actions supporting these processes. Genetic diversity, which is the allelic variation among individuals of a population, has been recognised as one of the pillars of resilient ecosystems. Genetic diversity within a population …

Shifting Soil Fungal Communities In Response To Fire And Weed Management In Urban Banksia Woodlands, Aaron Justin Brace

Theses: Doctorates and Masters

This research aims to fill the knowledge gap in soil fungi in the Banksia woodland and emphasizes considering holistic ecosystem dynamics in invasive species management strategies. This is accomplished by surveying soil fungi under different fire regime across the Swan Coastal Plain, and within both in and ex situ herbicide application trials. This is the first such study to investigate the fungal component of the Banksia woodland so thoroughly. Chapter 2 quantified and analysed changes in soil fungal community composition and functional groups over a 50-year fire chronosequence in fire-prone Banksia woodland in southwestern Australia. Effects were variable, but fungal …

Improving Growth Models Of Cultivated Sugar Kelp, Saccharina Latissima, By Accounting For Intraspecific Variation In Thermal Tolerance, Ruby Krasnow, Sara Gonzalez, Scott Lindell

Student Publications [Scholarly]

Dynamic models of sugar kelp (Saccharina latissima) growth are used to estimate the production potential of seaweed aquaculture in many regions around the world. These models do not currently account for the existence of S. latissima ecotypes that are adapted to regional environmental conditions, particularly temperature. We tested the hypothesis that recalibrating the temperature parameters of a dynamic energy budget model using literature data for S. latissima from regions with a similar climate to the region of interest would result in more accurate predictions than using a general species-wide temperature response curve. Calibrating the model using data from warm regions …

Leveraging Redundancy As A Link Between Spreading Dynamics On And Of Networks, Felipe Xavier Costa

Electronic Theses & Dissertations (2024 - present)

A constant quest in network science has been in the development of methods to identify the most relevant components in a dynamical system solely via the interaction structure amongst its subsystems. This information allows the development of control and intervention strategies in biochemical signaling and epidemic spreading. We highlight the relevant components in heterogeneous dynamical system by their patterns of redundancy, which can connect how dynamics affect network topology and which pathways are necessary to spreading phenomena on networks. In order to measure the redundancies in a large class of empirical systems, we develop the backbone of directed networks methodology, …

The Study Of Ribosome-Amplified Metabolism, Rambo, Effect In Vitro And In Live Cells, Jianchao Yu

Electronic Theses & Dissertations (2024 - present)

Quinary interactions arise due to the extreme macromolecular crowding inside live cells. Quinary interactions affect intracellular protein stability, activity, and homeostasis. Ribosomes, traditionally known for their role in protein synthesis, have been found to engage in quinary interactions with metabolic enzymes, modulating their activity and thereby revealing a potential regulatory role for ribosomes in cellular metabolism. This phenomenon, termed the Ribosome-Amplified MetaBOlism (RAMBO) effect, was investigated in this dissertation through a series of in vitro and in vivo studies using primarily Nuclear Magnetic Resonance (NMR) spectroscopy.

Firstly, an NMR-based direct enzyme assay compatible with ribosome was developed and validated using …

Transcription And Translation Regulation Of Germ Cell To Maternal Transition, Noor Kotb

Electronic Theses & Dissertations (2024 - present)

In sexually reproducing organisms, the process of gametogenesis produces mature eggs and sperms required for fertilization to occur. The egg's quality is crucial for the healthy development of the next generation, making oogenesis a tightly regulated process with multiple benchmarks. To investigate the intricacies of oogenesis, we utilized the Drosophila oogenesis system as our primary model. This choice was motivated by several factors. Firstly, the process of egg development in Drosophila is conserved across species, making it a valuable proxy for understanding oogenesis in other organisms, including humans. Secondly, Drosophila melanogaster has long been established as a powerhouse in genetic …

2024-2025 Report Of The Iucn Species Survival Commission And Secretariat, John P. Carroll, Rahul Kaul

Galliformes Specialist Group and Affiliated Societies: Reports and Other Materials

The Galliformes Specialist Group is committed to the worldwide conservation and sustainable management of all native populations of Galliformes species and their habitats.

Includes projected impact for 2021–2025, targets for 2021–2025, and statistics and information about the network, communications, and activities of the group for 2024–2025.

Valorization Of Spent Vetiver Roots For Biochar Generation, Sameer Neve, Dibyendu Sarkar, Manas Warke, Teresa Bandosz, Rupali Datta

Michigan Tech Publications

Vetiver root is widely used to produce essential oils in the aromatherapy industry. After the extraction of oil, the roots are disposed of as waste. The central objective of this research was to explore the conversion of this waste into a resource using a circular economy framework. To generate biochar, vetiver roots were pyrolyzed at different temperatures (300, 500, and 700 °C) and residence times (30, 60, and 120 min). Analysis showed the root biochar generated at 500 °C and held for 60 min had the highest surface area of 308.15 m2/g and a yield of 53.76%, in addition to …

Differential Conservation And Loss Of Chicken Repeat 1 (Cr1) Retrotransposons In Squamates Reveal Lineage-Specific Genome Dynamics Across Reptiles, Simone M. Gable, Nicholas A. Bushroe, Jasmine M. Mendez, Adam Wilson, Brendan J. Pinto, Tony Gamble, Marc Tollis

Biological Sciences Faculty Research and Publications

Transposable elements (TEs) are repetitive DNA sequences which create mutations and generate genetic diversity across the tree of life. In amniote vertebrates, TEs have been mainly studied in mammals and birds, whose genomes generally display low TE diversity. Squamates (Order Squamata; including ∼11,000 extant species of lizards and snakes) show as much variation in TE abundance and activity as they do in species and phenotypes. Despite this high TE activity, squamate genomes are remarkably uniform in size. We hypothesize that novel, lineage-specific genome dynamics have evolved over the course of squamate evolution. To understand the interplay between TEs and host …

It’S A Trap?! Escape From An Ancient, Ancestral Sex Chromosome System And Implication Of Foxl2 As The Putative Primary Sex-Determining Gene In A Lizard (Anguimorpha; Shinisauridae), Brendan J. Pinto, Stuart V. Nielsen, Kathryn A. Sullivan, Ashmika Behere, Shannon E. Keating, Mona Van Schingen-Khan, Truong Q. Nguyen, Thomas Ziegler, Jennifer Pramuk, Melissa A. Wilson, Tony Gamble

Biological Sciences Faculty Research and Publications

Although sex determination is ubiquitous in vertebrates, mechanisms of sex determination vary from environmentally to genetically influenced. In vertebrates, genetic sex determination is typically accomplished with sex chromosomes. Groups like mammals maintain conserved sex chromosome systems, while sex chromosomes in most vertebrate clades are not conserved across similar evolutionary timescales. One group inferred to have an evolutionarily stable mode of sex determination is Anguimorpha, a clade of charismatic taxa including monitor lizards, Gila monsters, and crocodile lizards. The common ancestor of extant anguimorphs possessed a ZW system that has been retained across the clade. However, the sex chromosome system in …

Dna Barcoding Reveals A New Population Of The Threatened Atlantic Forest Frog Sphaenorhynchus Canga, Diego J. Santana, Andre Yves, Elvis A. Pereira, Priscila S. Carvalho, Lucio M. C. Lima, Henrique C. Costa, Don Shepard

Biological Sciences Faculty Publications and Presentations

Species identification plays a significant role in biodiversity conservation. As many species remain unrecognized, particularly in neotropical hotspots like the Brazilian Atlantic Forest (AF), novel molecular techniques are being widely employed to bridge this gap. In this study, we used DNA barcoding and phylogenetic tools to identify a new population of Sphaenorynchus canga in the central region of the Brazilian AF. Our results extend the species’ known distribution by approximately 200 km to the south, encompassing a different mountain range than its type locality (Serra do Espinhaço). This disjunct distribution, while not uncommon among amphibians, suggests a historical connection between …

Myxomycetes Of Subantarctic Macquarie Island, Steven L. Stephenson

Biological Sciences Faculty Publications and Presentations

An expedition to subantarctic Macquarie Island was carried out during the period of late January to early May of 1995 with the objective of documenting myxomycete biodiversity. Collecting on the island yielded 412 field collections, with another 14 collections were obtained with the use of the moist chamber culture technique. A total of twenty-six species representing 13 genera was recorded. This is the largest set of data yet available on the myxomycetes associated with any high-latitude area of the Southern Hemisphere. Prior to the expedition, only a single species was known from Macquarie Island. The purpose of this paper is …

Optimization Of An Immune Assay To Detect Binding Of Nod2 To Staphylococcus Aureus, Precious Mckenzie

All Student Theses and Dissertations

Staphylococcus aureus, a gram-positive, commensal bacterium, is the cause of a multitude of opportunistic diseases and infections. While S. aureus has evolved ways to escape innate immune responses in the host, the mechanisms are not fully understood. One area of active research involves mechanisms by which S. aureus avoids detection by Pattern Recognition Receptors (PRRs), such as Nuclear Oligomerization Domain 2 (NOD2), present on the surface of and inside innate immune cells. This study aimed to design and optimize an assay that can be utilized to investigate S. aureus components that contribute to the activation of NOD2 receptors. The …

A Genus In The Bacterial Phylum Aquificota Appears To Be Endemic To Aotearoa-New Zealand, Jean F. Power, Carlo R. Carere, Holly E. Welford, Daniel T. Hudson, Kevin C. Lee, John W. Moreau, Anna-Louise Reysenbach, Thijs J.G. Ettema, Multiple Additional Authors

Biology Faculty Publications and Presentations

Allopatric speciation has been difficult to examine among microorganisms, with prior reports of endemism restricted to sub-genus level taxa. Previous microbial community analysis via 16S rRNA gene sequencing of 925 geothermal springs from the Taupō Volcanic Zone (TVZ), Aotearoa-New Zealand, revealed widespread distribution and abundance of a single bacterial genus across 686 of these ecosystems (pH 1.2-9.6 and 17.4-99.8 °C). Here, we present evidence to suggest that this genus, Venenivibrio (phylum Aquificota), is endemic to Aotearoa-New Zealand. A specific environmental niche that increases habitat isolation was identified, with maximal read abundance of Venenivibrio occurring at pH 4-6, 50-70 °C, and …