RESEARCH PROJECTS

I am a broadly trained plant physiologist/cell biologist having worked with algal nitrogen metabolism, herbicide mode of action and acquired herbicide resistance, and developmental biology and physiology of parasitic plants.

My current research involves the cell biology and physiology in marine systems, especially of freshwater and marine plants and algae. These organisms are the source of most carbon and nitrogen that is added to food chains in the coastal and freshwater areas. Macroalgae and higher plant representatives of these groups have the additional role of serving as sanctuary for the young of many animal species that share their habitat. In spite of their importance in these ecosystems, there are many gaps in our knowledge regarding their physiology and interaction between these and other organisms in these environments.

I am particularly interested in:

  • molecular interaction between seagrasses and pathogens that have led to massive die-off of seagrass beds in temperate areas around the world,
  • molecular mechanisms of stress tolerance in halophytic algae
  • nitrogen and carbon uptake and metabolism in marine algae and the plant species forming the large off-shore seagrass beds that line the coastal regions of the Gulf of Mexico, and difference between non-indigenous species (NIS) and the native species
  • cellular events involved in interactions between parasitic plants and their plant hosts

The seagrass pathogen, Labyrinthula, isolated from Zostera marina



MOST RECENT PUBLICATIONS
(* indicate undergraduate authors)

D. J. Shafer, S. Wyllie-Echeverria, and T. D. Sherman (2008) The Potential Role of Climate in the Distribution and Growth of the Introduced Seagrass Zostera japonica in North America. Aquatic Botany  (accepted)

T. D. Sherman, A. J. Bowling, T. W. Barger and  K. C. Vaughn (2008) The Vestigial Root of Dodder (Cuscuta pentagona) Seedlings. Int. J. Plant Sci. (accepted)

T. D. Sherman, E. Boone, A. B. Morris, A. Woodard*, E. Goldman*, D. L. Martin, C. Gautier*, and J. J. O’Brien (2008) Investigations of internal interactions between the parasitic barnacle Loxothylacus texanus (Rhizocephala: Sacculinidae) and its host Callinectes sapidus (Brachyura: Portunidae) using PCR techniques.  J. Crustacean Biology 28(2): 220-227 (in press)

D. J. Shafer, T. D. Sherman, and S. Wyllie-Echeverria, (2007) Do Desiccation Tolerances Control the Vertical Distribution of Intertidal Seagrasses?  Aquatic Botany 87(2): 161-166

J.B. James, T. D. Sherman, and R. Devereux (2006) "Analysis of bacterial communities in seagrass bed sediments by double-gradient denaturing gradient gel electrophoresis of PCR amplified 16S rRNA genes." Microbial Ecology   52(4):  655-661

J. Lartigue  and T. D. Sherman (2006) A Field Study of Nitrogen Storage and Nitrate Reductase Activity b in the Estuarine Macroalgae Enteromorpha lingulata (Chlorophyceae) and Gelidium pusillum (Rhodophyceae) Estuaries and Coasts 29(4): 699–708

N. Ueda*, C. Partridge, J. Bolland*, J. Hemming, T. Sherman, and A. Boettcher (2005) Effects of environmental estrogens on male gulf pipefish, Syngnathus scovelli (Evermann and Kendall). Bulletin of Environmental Contamination and Toxicology. 74(6):1207-1212 

J. Lartigue  and T. D. Sherman (2005) Response of Enteromorpha sp. (Chlorophyceae) to a nitrate pulse: nitrate uptake, inorganic nitrogen storage, and nitrate reductase activity. Marine Ecology Progress Series 292: 147–157

E. J. Boone, A. A. Boettcher, T. D. Sherman, and J. J. O’Brien (2004) What constrains the geographic and host range of the rhizocephalan Loxothylacus texanus in the wild?  Journal of Experimental Marine Biology and Ecology: 309: 129– 139

J.F. Valentine, E.F. Blythe, S. Madhavan, T.D. Sherman (2004) Effects of simulated herbivory on nitrogen enzyme levels, N-assimilation and N-allocation in Thalassia testudinum.  Aquatic Botany: 79: 235–255

E.J. Boone, A.B. Boettcher, T.D. Sherman and J.J. O’Brien  (2003) Characterization of settlement cues used by the Rhizocephalan barnacle, Loxothylacus texanus.  Marine Ecology Progress Series, 252: 187-197.

J. Lartigue and T. D. Sherman (2002) Field assays for measuring nitrate reductase activity in Enteromorpha sp. (Chlorophyceae), Ulva sp. (Chlorophyceae), and Gelidium sp. (Rhodophyceae), Journal Phycology, 38 (5): 971-982

H. Glenner J. Høeg, J. J. O'Brien and T.D. Sherman  (2000)  The invasive vermigon stage in the parasitic barnacles Loxothylacus texanus and L. panopaei (Sacculinidae): closing of the rhizocephalan life cycle. Marine Biology. 136: 249-257

T. D. Sherman, W. T. Pettigrew, and K.C. Vaughn  (1999)  Structural and immunological characterization of the Cuscuta pentagona L. chloroplast.  Plant Cell Physiology.  40: 592-603

 


CURRENT AND PENDING FUNDING

  • NOAA/NOS/NCCOS/CSCOR [SubContract-University of Mississippi] (2007-2012) Multistress 07:  Natural and Anthropogenic Disturbance in Coastal Gulf of Mexico Seagrass Communities.  [Pending]
  • NCUR-Lancy (2007-2008) Impact of Hurricanes on the Gulf Coast’s Critical Salt March Habitats.  [Pending]
  • MS-AL SeaGrant (2008-2009) Seagrass Bed Responses to Anthropogenic and Natural Stressors [Pending]
  • NSF-URM, ( Stress responses -How they Shape Ecological Interactions [Pending]
  • Alabama Center for Estuarine Studies (2007-2009) “Interactions between Native and Non-native Plants in the Mobile-Tensaw Delta” [Funded]
  • National Science Foundation (2001-2006) RUI Collaborative Proposal: Mechanisms of Induced Pathogen Resistance in Seagrasses. (Co-PIs: Dr. Anne Boettcher, Dr. Thomas Arnold, Dr. Christopher Tanner)
 
CURRENT GRADUATE STUDENTS

Fnu Simmi will begin working in my lab in the Fall of 2007.  She will be involved in be working with ultrastructural characterization on of Labyrinthula infections of seagrasses.

 


UNDERGRADUATE AND GRADUATE STUDENTS RECENTLY WORKING IN THE LAB

Crystal Welch (Undergrad) Ultrastructural analysis of the seagrasses Thalassia testudinum and Zostera marina under pathogenic attack by Labyrinthula zosterae and Labyrinthula sp. (Crystal worked in my lab during the summer of 2005. She was a student at Howard University.  She is now in medical school.)

Godi Galiher (undergrad) Ultrastructural and immunocytochemical analysis of cell wall structure in the seagrass Thalassia testudinum under pathogenic attack by Labyrinthula sp. (Jodi worked in my lab during the summer of 2004 and has recently completed her B.S. at Seattle Pacific College.)

Kerry Evans   (undergrad)   Ultrastructural and immunocytochemical analysis of cell wall structure in the seagrass Thalassia testudinum under pathogenic attack by Labyrinthula sp. (Kerry worked in my lab during the summer of 2003 and has gone on to pursue graduate work at that Univ. of Alabama in Genetics)

Lana Vojvodic (grad) She worked in my lab on a project to characterize the relationship between trichomycetes and their insect hosts. She is using transmission electron microscopy to study this interaction at high resolution. Lana gone on to enter the doctoral program in the Dept of Entomology at Auburn University.

Nobuo Ueda (undergrad at time of research) Evaluation of the effects of 17a-ethinylestradiol on non-brooding male Gulf pipefish, Syngnathus scovelli. Nobuo has since entered our graduate program and is working in the lab of Dr. Anne Boettcher.

Charlyn Partridge (grad) Comparison of two methods for the determination of vitellogenin levels in the Gulf pipefish, Syngnathus scovelli. After completing her M.S. degee with Dr. Anne Boettcher, Charlyn has gone on to work on her doctoral degree at Texas A&M University.

PREVIOUS GRADUTE STUDENTS

Deborah Shafer (Ph.D. - Dept. of Marine Sciences) The Invasive Seagrass Zostera japonica : Distribution, Autecology, and Potential for Expansion (2007)

Anna Penton (M.S. - Dept. of Biology)  Anna's work centered on community structure across invasive and indigenous aquatic plants.  She will graduate in the fall of 2006 and will work in a medical research lab here at the Univ. of South Alabama. (2006)

Joe James (M.S. - Dept. of Biology). Molecular Characterization of Diversity of Bacteria Associated with Seagrass Transplanting Units and Seagrass Bed Sediments. (2004)

Julien Lartigue (Ph.D. - Dept. of Marine Sciences) Nitrate Uptake, Nitrogen Storage, and Nitrate Reductase Activity in Estuarine Enteromorpha Sp. (Chlorophyceae) (2002)

Fennel Blythe (M.S. - Dept. of Biology) Nitrogen Uptake, Assimilation, and Translocation in the Seagrass, Thalassia Testudinum (1996)
COURSES TAUGHT
 
     
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