2004 Progress Report: Linking Population and Physiological Diversity in a Toxin-producing Dinoflagellate

EPA Grant Number: R830413
Title: Linking Population and Physiological Diversity in a Toxin-producing Dinoflagellate
Investigators: Campbell, Lisa , Gold, John R.
Institution: Texas A & M University
EPA Project Officer: Hiscock, Michael
Project Period: September 1, 2002 through August 31, 2005 (Extended to February 28, 2007)
Project Period Covered by this Report: September 1, 2003 through August 31, 2004
Project Amount: $464,880
RFA: Ecology and Oceanography of Harmful Algal Blooms (2002) RFA Text |  Recipients Lists
Research Category: Water Quality , Ecosystems , Water , Aquatic Ecosystems


The objective of this research project is to understand the dynamics of blooms of the toxic dinoflagellate, Karenia brevis, in the Gulf of Mexico. Preliminary results have demonstrated that clonal cultures of K. brevis can have significantly different rates of growth and levels of toxin production when grown under identical conditions. Our goal is to develop new hypervariable molecular markers (microsatellites) for K. brevis to link population and physiological diversity in K. brevis. Ultimately, this information will be used to predict the response of K. brevis at the population level to environmental changes and to assess how these responses affect and influence bloom formation and dynamics. The specific objectives of this research project are to: (1) optimize a suite of hypervariable, nuclear-encoded DNA markers (microsatellites) to characterize genetic diversity among strains of the toxic dinoflagellate, K. brevis; (2) isolate and establish clonal cultures of K. brevis sampled during the onset, bloom, and decline of a toxic algal bloom event; and (3) utilize the highly polymorphic molecular markers to elucidate population structure.

Progress Summary:

Three microsatellite loci have been identified, and alleles at each locus have been characterized for K. brevis isolates in our culture collection. Preliminary results have shown that a number of markers appear to be useful for fingerprinting clones of other dinoflagellate families, as well as for both K. brevis and K. mikimotoi. The capability to positively differentiate both between and among individual clones of K. brevis and K. mikimotoi is significant and potentially represents an extremely useful tool. Because of the difficulty for routine identification of these strains, as well as the apparent variation in toxicity among strains/clones within each of these species, the markers identified may be applicable for development of simple fingerprinting assays for routine use by managers.

Future Activities:

We will focus on the following in Year 3 of the project: (1) complete identification and characterization of 10 to 15 microsatellites; (2) isolate and establish clonal cultures of K. brevis sampled during the onset, bloom, and decline of a toxic algal bloom event and assess genetic and physiological variability within a bloom population; (3) determine allele distributions at 10 to 15 (independent) microsatellites among spatial and temporal isolates of K. brevis, including clones currently in culture; and (4) determine growth rates for genetically distinct clones to assess physiological variability within and among K. brevis haplotypes.

Journal Articles on this Report : 1 Displayed | Download in RIS Format

Other project views: All 21 publications 6 publications in selected types All 5 journal articles
Type Citation Project Document Sources
Journal Article Mikulski CM, Morton SL, Doucette GJ. Development and application of LSU rRNA probes for Karenia brevis in the Gulf of Mexico, USA. Harmful Algae 2005;4(1):49-60. R830413 (2004)
R830413 (Final)
  • Full-text: Science Direct
  • Abstract: Science Direct
  • Other: Science Direct
  • Supplemental Keywords:

    phytoplankton ecology, molecular genetics, marine, estuarine, coastal, population diversity , ecology and ecosystems, genetics, molecular biology/genetics, oceanography, algal blooms, Karenia brevis, algal bloom detection, bloom dynamics, brevetoxins, dinoflagellate, dinoflagellate blooms, gene sequences, marine biotoxins, marine ecosystem, marine toxins,, RFA, Scientific Discipline, Water, Ecosystem Protection/Environmental Exposure & Risk, Oceanography, algal blooms, Biochemistry, Ecological Risk Assessment, Ecology and Ecosystems, marine ecosystem, toxin monitoring programs, marine biotoxins, bloom dynamics, brevetoxins, phytoplankton, gene sequences, dinoflagellate, algal bloom detection, dinoflagellate blooms, K. brevis, Karenia brevis

    Progress and Final Reports:

    Original Abstract
  • 2003 Progress Report
  • 2005 Progress Report
  • 2006
  • Final Report