A5043947022- Insect and Arachnid Ecology and Behavior
- Protist diversity and phylogeny
- Plant and animal studies
- Microbial Community Ecology and Physiology
- Genomics and Phylogenetic Studies
- Insect and Pesticide Research
- Legume Nitrogen Fixing Symbiosis
- Animal Behavior and Reproduction
- Insects and Parasite Interactions
- RNA and protein synthesis mechanisms
- Ecology and Vegetation Dynamics Studies
- Plant Parasitism and Resistance
- Methane Hydrates and Related Phenomena
- Parasite Biology and Host Interactions
- Diatoms and Algae Research
- Photosynthetic Processes and Mechanisms
- Insect symbiosis and bacterial influences
- Algal biology and biofuel production
- Reproductive tract infections research
- Parasitic Infections and Diagnostics
- Marine and coastal plant biology
- Evolutionary Game Theory and Cooperation
- Cellular transport and secretion
- RNA Research and Splicing
- Plant Pathogens and Resistance
Arizona State University
2016-2025
Tempe Union High School District
2019
Dalhousie University
2011-2015
Canadian Institute for Advanced Research
2006-2015
University of British Columbia
2006-2015
A group of protist experts proposes a two-step DNA barcoding approach, comprising universal eukaryotic pre-barcode followed by group-specific barcodes, to unveil the hidden biodiversity microbial eukaryotes.
Cryptophyte and chlorarachniophyte algae are transitional forms in the widespread secondary endosymbiotic acquisition of photosynthesis by engulfment eukaryotic algae. Unlike most plastid-bearing algae, miniaturized versions endosymbiont nuclei (nucleomorphs) persist cryptophytes chlorarachniophytes. To determine why, to address other fundamental questions about eukaryote-eukaryote endosymbiosis, we sequenced nuclear genomes cryptophyte Guillardia theta Bigelowiella natans. Both have >21,000...
Plastids are supported by a wide range of proteins encoded within the nucleus and imported from cytoplasm. These plastid-targeted may originate endosymbiont, host, or other sources entirely. Here, we identify characterise 770 that conserved across ochrophytes, major group algae including diatoms, pelagophytes kelps, possess plastids derived red algae. We show ancestral ochrophyte plastid proteome was an evolutionary chimera, with 25% its phylogenetically tractable nucleus-encoded deriving...
The division of life into producers and consumers is blurred by evolution. For example, eukaryotic phototrophs can lose the capacity to photosynthesize, although they may retain vestigial plastids that perform other essential cellular functions. Chrysophyte algae have undergone a particularly large number photosynthesis losses. Here, we present plastid genome sequence from nonphotosynthetic chrysophyte, "Spumella" sp. NIES-1846, show it has retained nearly identical set plastid-encoded...
The complex plastid of the cryptophyte Guillardia theta and diatom Phaeodactylum tricornutum can both be traced back to an engulfed eukaryotic red alga. origin these plastids is most obvious in cryptophytes, where organelle still possesses a remnant nucleus, nucleomorph. nucleomorph itself embedded periplastid compartment (PPC), former algal cytosol. In diatom, surrounded by 4 membranes, outer one being continuous with host rough endoplasmatic reticulum. recent report, we have shown that...
The internal compartmentation of eukaryotic cells not only allows separation biochemical processes but it also creates the requirement for systems that can selectively transport proteins across membrane boundaries. Although most function in a single subcellular compartment, many are able to enter two or more compartments, phenomenon known as dual multiple targeting. aminoacyl-tRNA synthetases (aaRSs), which catalyze ligation tRNAs their cognate amino acids, particularly prone functioning...
ABSTRACT The symbiosis between termites and their hindgut protists is mutually obligate vertically inherited. It was established by the late Jurassic in cockroach ancestors of as they transitioned to wood feeding. Since then, protist symbionts have been transmitted from host generation proctodeal trophallaxis (anal feeding). belong multiple lineages within eukaryotic superphylum Metamonada. Most these evolved large cells with complex morphology, unlike non‐termite‐associated species richness...
Background For the majority of microbial eukaryotes (protists, algae), there is no clearly superior species concept that consistently applied. In absence a practical biological concept, most and genus level delineations have historically been based on morphology, which may lead to an underestimate diversity eukaryotes. Indeed, growing body molecular evidence, such as barcoding surveys, beginning support conclusion significant cryptic exists. This appears be due combination using morphology...
A non-canonical nuclear genetic code, in which TAG and TAA have been reassigned from stop codons to glutamine, has evolved independently several eukaryotic lineages, including the ulvophycean green algal orders Dasycladales Cladophorales. To study phylogenetic distribution of standard codes, we generated sequence data a representative set algae used robust phylogeny evaluate different evolutionary scenarios that may account for origin code. This demonstrates Cladophorales share this...
Colpodellids are free-living, predatory flagellates, but their close relationship to photosynthetic chromerids and plastid-bearing apicomplexan parasites suggests they were ancestrally photosynthetic. may therefore retain a cryptic plastid, or have lost plastids entirely, like the Cryptosporidium. To find out, we generated transcriptomic data from Voromonas pontica ATCC 50640 searched for homologs of genes encoding proteins known function in apicoplast, non-photosynthetic plastid...
Abstract Coptotermes formosanus Shiraki and gestroi (Wasmann) (Blattoidea: Rhinotermitidae) are invasive subterranean termite pest species with a major global economic impact. However, the descriptions of mutualistic protist communities harbored in their respective hindguts remain fragmentary. The C. hindgut has long been considered to harbor three species, Pseudotrichonympha grassii (Trichonymphida), Holomastigotoides hartmanni , Cononympha ( Spirotrichonympha ) leidyi...
Calonymphids are a group of multinucleate, multiflagellate protists belonging to the order Cristamonadida (Parabasalia) that found exclusively in hindgut termites from family Kalotermitidae. Despite their impressive morphological complexity and diversity, few species have been formally described fewer still characterized at molecular level. In this study, four novel calonymphids were isolated characterized: Calonympha chia Snyderella yamini spp. nov., Neotermes castaneus Calcaritermes...
Secondary plastids are acquired by the engulfment and retention of eukaryotic algae, which results in an additional surrounding membrane or pair membranes relative to more familiar primary land plants. In most cases, endocytosed alga loses its genome as it becomes integrated, but two algal groups, cryptophytes chlorarachniophytes, secondary retain a vestigial nucleus periplastidal compartment (PPC), remnant cytoplasm between inner outer pairs. Many essential housekeeping genes missing from...
Chlorarachniophytes are a small group of marine photosynthetic protists. They best known as examples an intermediate stage secondary endosymbiosis: their plastids derived from green algae and retain highly reduced nucleus, called nucleomorph, between the inner outer pairs membranes. can be challenging to identify species level, due size, complex life cycles, fact that even genus-level diagnostic morphological characters observable only by EM. Few have been formally described, many available...
The systematics of the green algal class Ulvophyceae have been difficult to resolve with ultrastructural and molecular phylogenetic analyses. Therefore, we investigated relationships among ulvophycean orders by determining distribution two discrete genetic characters previously identified only in order Dasycladales. First, Acetabularia acetabulum uses core translation GTPase Elongation Factor 1alpha (EF-1alpha) while most Chlorophyta instead possess related Factor-Like (EFL). Second, nuclear...
The eukaryotic elongation factor EF-1alpha (also known as EF1A) catalyzes aminoacyl-tRNA binding by the ribosome during translation. Homologs of this essential protein occur in all domains life, and it was previously thought to be ubiquitous eukaryotes. Recently, however, a number eukaryotes were found lack instead encode related called EFL (for EF-Like). EFL-encoding organisms are scattered widely across tree eukaryotes, have close relatives that EF-1alpha. This intriguingly complex...
Abstract Dinoflagellates are some of the most common eukaryotic cells in ocean, but have very unusual nuclei. Many exhibit a form closed mitosis (dinomitosis) wherein nuclear envelope (NE) invaginates to one or more trans-nuclear tunnels. Rather than contact spindles directly, chromatids then bind membrane-based kinetochores on NE. To better understand these unique mitotic features, we reconstructed architecture Polykrikos kofoidii 3D using focused ion beam scanning electron microscopy...