Center Facilities

Our facilities and resources are available to the research community on a collaborative basis year-round. Formal outreach presentations and training sessions are scheduled on an as-needed basis in Miami-Dade, Florida, nationally, and internationally.

Toxin Probes

In collaboration with the Florida International University Southeast Environmental Research Center, the University of North Carolina (Wilmington) Center for Marine Research, and the Virginia Institute of Marine Science, our research objectives are to promote collaborative studies on marine and freshwater toxins by providing a facility for the culture of toxic microorganisms and isolation of raw materials to identify new toxins, examine the molecular basis of toxicity, investigate the metabolism and fate of toxins, and study biosynthesis. All marine toxins used in Center operation, with the exception of tetrodotoxin are produced within this facility.

Dinoflagellate cells are mass cultured in 10 Liter carboys to peak density. Depending upon the species, toxins can be extracted from cells that have been physically separated from the culture medium or extracted with a solvent.

Toxins are purified by thin-layer chromatography, column chromatography, high performance liquid chromatograph, and/or isoelectric focusing. Culture, isolation, and purification procedures for the production of the toxins, brevetoxins, and okadaic acid are routine. Saxitoxin-producing cultures are also grown in mass culture and the major toxins are separated. Ciguatoxin and maitotoxin producers are under current examination.

Please contact Dr. Kelly Rein at Florida International University's Department of Chemistry for more information.

In Vitro In Vivo Fish Culture

This facility provides resources for the development and manipulation of model systems involving selected aquatic animals with emphasis placed on assays using cell cultures and whole animals. The major service components include a cell culture and analysis laboratory, a damselfish tumor induction facility, a transgenic zebrafish facility, hatchery facility, and access to an electron microscopy laboratory and environmental exposure system.

Many of the Centers' ongoing and planned research projects will utilize cultured cells for morphological, physiological, electrophysical, and biochemical studies. This facility will provide all resources necessary for set-up, maintenance, and analysis of cell cultures from aquatic fish and invertebrates. This will include assistance in developing new techniques for specialized needs as well as the application of routine procedures for cell maintenance and manipulation.

Access to transmission and scanning electron microscopy (including x-ray elemental analysis of specimens) will be facilitated by funding microscope use fees, providing supplies necessary for preparation of tissues and cultured cells, and providing access to a technician with expertise in all facets of electron microscopy.

For more information, contact Dr. Mike Schmale at the University of Miami Rosenstiel School of Marine and Atmospheric Science.

Toxicogenomics

Overview: Several positive developments have coalesced to point out the strong need for the implementation of this core. First, it is clear that NIEHS, both intramurally and extramurally, has committed strongly to this area of research, and we wish to be responsive to trends within the NIEHS. Second, the supplemental funds awarded to our Center provided us with the opportunity to test the feasibility of performing research in this area. These initial studies were very successful: a) as indicated in the Toxins Research core above, the Center was able to examine the genomic effects of PbTx and to falsify the hypothesis that PbTx was acting via the AhR receptor. These studies were a successful use of commercially available Mouse array, and utilized the expertise and analysis tools of the UM Microarray Facility. The results have been presented at a scientific meeting and are being prepared for publication. b) Data is being analyzed obtained using Fundulus (killifish) arrays for copper, PbTx and BNF exposed fish. Third, UM has made a substantial investment in equipment and manpower. Fourth, the Center has recruited an internationally recognized expert in fish functional genomics (Crawford). Fifth, the Center has received significant funds from NIEHS (via MDIBL and the R33 mechanism) to generate sequence information for a Comparative Toxicogenomics Database. Sixth, the UM and NIEHS funds were leveraged to obtain a grant from NSF to purchase the sequencer for the facility. All of these developments pointed positively towards the establishment in 2003 of a Toxicogenomics Core.

Facilities and Equipment: During 2003 this core IS BEING assembled and made operational. While it is still a bit early to define the exact nature of this core, several aspects are envisioned. (1) It will be co-directed by an expert in genomics (Crawford) and an expert in aquatic toxicology (Grosell), and both will receive advice and consultation from the IAC and EAC as well as a UM Genomics Steering Committee. These groups will to establish priorities for sequencing and array experiments.

As of this writing, the following instrumentation has been procured: Stratagene MX4000 Quantitative PCR Machine; Agilent 2100 Bioanalyzer; ABI 3730 (48 capillary) DNA Sequencer; microbiological equipment to mass process clones, an array reader (Axon), computers and software for bioinformatics, robotic equipment for clone processing, MJ Tetrad PCR machines, additional electrophoresis capability for clone verification. All equipment and service contracts will come from the UM and NSF grants. Investigators will also have access to liquid handling robotics (Packard) and an arrayer (Gene Machines Omnigrid) at the UM Medical campus.

For more information, contact Dr Douglas Crawford or Dr. Martin Grosell at the University of Miami Rosenstiel School of Marine and Atmospheric Science.

Neurophysiology

This facility core consists of a single-cell photometry system and two single-cell patch clamp rigs and accessories. This facility provides equipment and expertise relevant to single cell electrophysiological studies. Recently, one rig has been used to study the actions of the brevetoxins on single Na channel physiology. The goals of this project have been two-fold: to understand the multiple excitatory and depressive effects of PbTx-3 on neurons of the rat brain and to understand the differences in actions of the brevetoxin derivatives compared to native toxin. This project is closely aligned with the toxin research core and the derivatives produced therein.

The other rig has been used recently for studies of animal models and is closely aligned with the animal models research core. Two models used are Aplysia (as a neurophysical model) and damselfish (as a model of human disease neurofibromatosis type 1 - NF1). The latter model has recently expanded to the first study of the electrophysiology of human Schwann cells involved in NF1.

For more information contact Dr. Lynne Fieber at the University of Miami Rosenstiel School of Marine and Atmospheric Science.