A5026258627- Retinal Development and Disorders
- Fish biology, ecology, and behavior
- Animal Behavior and Reproduction
- Neurobiology and Insect Physiology Research
- Ichthyology and Marine Biology
- Aquatic Ecosystems and Biodiversity
- Genetic diversity and population structure
- Photoreceptor and optogenetics research
- Atmospheric Ozone and Climate
- Genomics and Phylogenetic Studies
- Spectroscopy and Laser Applications
- Zebrafish Biomedical Research Applications
- Advanced Chemical Physics Studies
- Coral and Marine Ecosystems Studies
- Amphibian and Reptile Biology
- Chromosomal and Genetic Variations
- Identification and Quantification in Food
- Congenital heart defects research
- Semiconductor materials and interfaces
- Atmospheric chemistry and aerosols
- Aquaculture disease management and microbiota
- Animal Genetics and Reproduction
- Genetic Mapping and Diversity in Plants and Animals
- Physiological and biochemical adaptations
- Plant and animal studies
University of Maryland, College Park
2013-2022
University of Maryland, Baltimore
2019
Western Colorado University
2017
Agrobioinstitute
2012
University of New Hampshire
1997-2011
Alberta Medical Association
2009
University of Connecticut
2007
University College London
2006
Physical Sciences (United States)
1991-1995
University of California, Berkeley
1990-1991
Cichlid fishes are famous for large, diverse and replicated adaptive radiations in the Great Lakes of East Africa. To understand molecular mechanisms underlying cichlid phenotypic diversity, we sequenced genomes transcriptomes five lineages African cichlids: Nile tilapia (Oreochromis niloticus), an ancestral lineage with low diversity; four members lineage: Neolamprologus brichardi/pulcher (older radiation, Lake Tanganyika), Metriaclima zebra (recent Malawi), Pundamilia nyererei (very recent...
Vertebrate vision is accomplished through light-sensitive photopigments consisting of an opsin protein bound to a chromophore. In dim light, vertebrates generally rely on single rod [rhodopsin 1 (RH1)] for obtaining visual information. By inspecting 101 fish genomes, we found that three deep-sea teleost lineages have independently expanded their
We constructed a second-generation linkage map of tilapia from the F(2) progeny an interspecific cross between Oreochromis niloticus and aureus. The reported here contains 525 microsatellite 21 gene-based markers. It spans 1311 cM in 24 groups, for average marker spacing 2.4 cM. detected associations sex red color with markers on group 3. This will enable mapping selective breeding quantitative traits important to economic culture as food fish contribute study closely related cichlids that...
Spectral tuning of visual pigments is typically accomplished through changes in opsin amino acid sequence. Within a given class, at few key sites control wavelength specificity. To investigate known differences the pigment spectral sensitivity Lake Malawi cichlids, Metriaclima zebra (368, 488, and 533 nm) Dimidiochromis compressiceps (447, 536, 569 nm), we sequenced cone genes from these species as well Labeotropheus fuelleborni Oreochromis niloticus. These cichlids have five distinct...
The evolution of cone opsin genes is characterized by a dynamic process gene birth and death through duplication loss. However, the forces governing retention are poorly understood. African cichlid fishes have range ecologies, differing in habitat foraging style, which make them ideal for examining selective acting on family. In this work, we present data riverine cichlid, Oreochromis niloticus, an ancestral outgroup to adaptive radiations Great lakes. We identify 7 with several instances...
A major goal of evolutionary biology is to unravel the molecular genetic mechanisms that underlie functional diversification and adaptation. We investigated how changes in gene regulation coding sequence contribute sensory two replicate radiations cichlid fishes. In clear waters Lake Malawi, differential opsin expression generates diverse visual systems, with sensitivities extending from ultraviolet red regions spectrum. These fall into three distinct clusters are correlated foraging habits....
Cichlid fishes have radiated into hundreds of species in the Great Lakes Africa. Brightly colored males display on leks and vie to be chosen by females as mates. Strong discrimination causes differential male mating success, rapid evolution color patterns and, possibly, speciation. In addition differences pattern, Lake Malawi cichlids also show some largest known shifts visual sensitivity among closely related species. These result from modulated expression seven cone opsin genes. However,...
Abstract Lake Victoria cichlids are one of the most speciose groups vertebrates. Selection on coloration is likely playing an important role in their rapid speciation. To test hypothesis that sensory biases could explain species differences mating preferences and nuptial coloration, we studied seven populations four closely related genus Pundamilia differ visual environment male colour. Microspectrophotometry determined wavelength maximum absorption (λ max ) rod pigment three cone pigments...
Single-gene and whole-genome duplications are important evolutionary mechanisms that contribute to biological diversification by launching new genetic raw material. For example, the evolution of animal vision is tightly linked expansion opsin gene family encoding light-absorbing visual pigments. In teleost fishes, most species-rich vertebrate group, opsins particularly diverse key successful colonization habitats ranging from bioluminescence-biased but basically dark deep sea clear mountain...
African cichlid fishes are well known for their rapid radiations and a model system studying evolutionary processes. Here we compare multiple, high-quality, chromosome-scale genome assemblies to elucidate the genetic mechanisms underlying diversification study how structure evolves in rapidly radiating lineages. We re-anchored our recent assembly of Nile tilapia (Oreochromis niloticus) using new high-density map. also developed de novo Lake Malawi cichlid, Metriaclima zebra, high-coverage...
Cichlid fish inhabit a diverse range of environments that vary in the spectral content light available for vision. These differences should result adaptive selective pressure on genes involved visual sensitivity, opsin genes. This study examines evidence differential molecular evolution East African cichlid due to gross environmental conditions. First, we characterize regime experienced by using likelihood ratio test format, comparing models with different constraints relative rates amino...
We have developed (CA) n microsatellite markers for the cichlid fish, Oreochromis niloticus using a variation of hybrid capture method. The resulting genomic library was highly enriched in repetitive DNA with 96% clones containing CA repeats. number repeats ranged from four to 45 an average 19. Two‐thirds sequenced had 12 or more and sufficient flanking sequence design primers. were tested F 2 cross O. × aureus . Nearly 90% amplified this 74% these informative. This work demonstrates...
Animals use their sensory systems to detect information about the external environment in order find mates, locate food and habitat avoid predators. Yet, there is little understanding of relative amounts genetic and/or environmental variation system properties. In this paper, we demonstrate opsin expression a population bluefin killifish. We measured five opsins (which correlates with frequency corresponding cones) using quantitative, real-time polymerase chain reaction for offspring from...
Sensory systems provide crucial information about an organism's external environment and, thus, are often subject to strong natural selection. Because of the large variation in intensity and spectral quality light aquatic environments, studies sensory adaptation have focused on visual fish for over a half century. Recently, molecular genetic mechanisms that determine sensitivity pigments been characterized several fishes including zebrafish, guppies, medaka, killifish, bream, cichlids. The...
Phenotypic evolution may occur either through alterations to the structure of protein-coding genes or their expression. Evidence for which these two mechanisms more commonly contribute a phenotype can be garnered from examples parallel and convergent evolution. The visual system East African cichlid fishes is an excellent with address this question. Cichlid Lakes Malawi (LM) Victoria together exhibit three diverse palettes coexpressed opsins several important mutations that both shift...
Sensory systems play crucial roles in survival and reproduction. Therefore, sensory plasticity has important evolutionary implications. In this study, we examined retinal five species of cichlid fish from Lake Malawi. We compared the cone opsin expression profiles wild-caught to lab-reared F1 that had been raised a UV minus, reduced intensity light environment. All genes were expressed also individuals. However, found statistically significant differences relative among all species. The most...
In response to increasing calls for the reform of undergraduate science curriculum life majors and pre-medical students (Bio2010, Scientific Foundations Future Physicians, Vision & Change), an interdisciplinary team has created NEXUS/Physics: a repurposing introductory physics sciences. The interacts strongly supportively with biology chemistry courses taken by life-science students, goal helping build general, multi-discipline scientific competencies. NEXUS/Physics stresses examples...
Vision frequently mediates critical behaviours, and photoreceptors must respond to the light available accomplish these tasks. Most are thought contain a single visual pigment, an opsin protein bound chromophore, which together determine spectral sensitivity. Mechanisms of tuning include altering opsin, changing chromophore incorporating pre-receptor filtering. A few exceptions use pigment have been documented in mature photoreceptor coexpresses opsins that form spectrally distinct pigments,...