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Department of Biology University of St. Thomas, Minnesota USA

 

Amy S. Verhoeven, Ph.D

Research in Plant Physiology

 

Professional Interests:

I am a plant physiologist/ biochemist with interests in how plants acclimate and adapt to stressful environments.  I am particularly interested in photosynthesis and photoprotective strategies that plants use in times of stress.  

My research has focused on low temperature stress over the last several years, and the questions I have been asking center on how plants deal with high light intensities during winter, when photosynthesis is limited.  My lab projects have involved examining a  process called xanthophyll-cycle dependent energy dissipation, and also leaf antioxidant systems.

 

Current Projects
 

A current major research focus is to understand how changes in photosynthetic efficiency during winter relate to changes in the relative abundance of, and arrangement of, the various light harvesting and reaction center proteins of the photosynthetic apparatus.  To do this we are developing antibodies to the proteins of interest in order to quantify seasonal changes in abundance.  Additionally, we are developing green gel assays to look at changes in arrangement of proteins.  Eventually we will utilize the green gels to look at pigment profiles of the various protein complexes.

  A second research project has been examining the antioxidant enzymes and metabolites in several conifer species, and studying how the activity and levels of these molecules change seasonally.

 

 

Recent Publications and Presentations
Student names are in bold.

Verhoeven AS, Swanberg A, Thao M,  Whiteman J (2005)  Seasonal changes in leaf antioxidant systems and xanthophyll cycle characteristics in Taxus x media growing in sun and shade environments.  Physiologia Plantarum 123:428-434

 

Bachman KM, Ebbert B, Adams WWIII, Verhoeven AS, Logan BA, Demmig-Adams B (2004) Effects of lincomycin on PSII efficiency, non-photochemical quenching, D1 protein and xanthophyll cycle during photoinhibition and recovery.  Functional Plant Biology 31(8):803-813

Barker DH, Adams WWIII, Demmig-Adams B, Logan BA, Verhoeven AS, Smith SD (2002)  Nocturnally retained zeaxanthin does not remain engaged in a state primed for energy dissipation during the summer in two Yucca species growing in the Mojave Desert.  Plant Cell and Environment   25: 95-103

Hieber DA, Bugos RC, Verhoeven AS, Yamamoto HY (2002)  Overexpression of violaxanthin de-epoxidase:  properties of C-terminal deletions on activity and pH dependent lipid binding.   Planta  214:476-483

Verhoeven AS, Bugos B, Yamamoto H (2001)  Transgenic tobacco with suppressed zeaxanthin formation is susceptible to stress-induced photoinhibition.  Photosynthesis Research  67:27-39.

Sun W-H, Verhoeven AS, Bugos RC, Yamamoto HY (2001) Suppression of zeaxanthin formation does not reduce photosynthesis and growth of transgenic tobacco plants under field conditions.  Photosynthesis Research 67:41-50.

Verhoeven AS, Adams WWIII, Demmig-Adams B, Croce R, Bassi R  (1999) Xanthophyll cycle pigment localization and dynamics during exposure to low temperatures and light stress in Vinca major.  Plant Physiology 120:727-734.

Verhoeven AS, Adams WWIII, Demmig-Adams B  (1999) The xanthophyll cycle and acclimation of Pinus ponderosa and Malva neglecta to winter stress. Oecologia 118: 277-287

Verhoeven AS, Adams WWIII, Demmig-Adams B  (1998) Photoinhibition during winter stress in sun and shade Euonymus kiautschovicus leaves; the xanthophyll cycle and leaf adenylate status. Plant Cell and Environment  21: 893-903

 

                       

 

Published Abstracts / Student Presentations:  

Morales Paul C, Tangen Mike S, Verhoeven Amy S (2005)  Seasonal changes in relative abundance and phosphorylation status of light harvesting and reaction center proteins in Pinus strobus and Abies balsamea.  American Society of Plant Biology Abstract Supplement, Abstract # 176  (poster presentation)

 

 

Verhoeven Amy S (2005)  Investigating the induction of the CAM photosynthetic pathway in Mesembryanthemum crystallinum, an inquiry-based laboratory. American Society of Plant Biology Abstract Supplement, Abstract # 1159 (poster presentation)

Osmolak Angela, Suurmeyer Laura, Verhoeven Amy (September, 2005) Seasonal changes in relative abundance and phosphorylation status of photosynthetic proteins in sun and shade balsam fir (Abies balsamea).  Inquiry at UST Symposium (poster presentation)

 Blissenbach Mike, Verhoeven Amy (September 2006) Analysis of Protein Changes Associated With Photosynthetic Recovery in Winter Stressed Conifers. Inquiry at UST Symposium (poster presentation)

Osmolak Angela, Crow Jordan, Verhoven Amy (September 2006) Seasonal changes in relative abundance and phosphorylation status of light harvesting and reaction center proteins in Pinus strobus and Abies balsamea. Inquiry at UST Symposium (poster presentation)

Broeren, Margaret and Amy Verhoeven (2004)  The role of chlorophyll fluorescence methodology in Fv/Fm recovery from light stress. Journal of the Minnesota Academy of Science 68:  17

Farrell, Leigh (2004)  Method development and study of the winter rearrangement of the photosystems in conifers. Journal of the Minnesota Academy of Science 68:  19

Verhoeven AS, Swanberg A, Thao, M, Whitman J (2002) Seasonal changes in leaf antioxidant systems in the evergreen Taxus cuspidate growing in sun and shade environments.  American Society of Plant Biology Abstract Supplement, Abstract # 668

 
Swanberg A, Whiteman J and Verhoeven A (March 2003) Seasonal changes in photoprotective mechanisms of the evergreen Taxus cuspidata growing in sun and shade environments. Midwest Regional Meeting of American Society of Plant Biologists, Iowa State University, Ames IA (Oral presentation)
 

Swanberg, Andrea and Amy Verhoeven (2002)  Seasonal acclimation of leaf antioxidant systems in the evergreen Taxus cuspidate growing in sun vs. shade. Journal of the Minnesota Academy of Science 66:  30  

Thao, Mai and Amy Verhoeven (2002)  Seasonal variation in antioxidant activities of APX, GR, and SOD in the evergreen Taxus cuspidate growing under sun and shade.  Journal of the Minnesota Academy of Science 66:  31

 

Inquiry at UST Poster Presentations
 

Summer 2006

 


Angela Osmolak

Angela Osmolak & Jordan Crow

Seasonal changes in relative abundance and phosphorylation status of light harvesting and reaction center proteins in Pinus strobus and Abies balsamea.

Click here to read the entire abstract

 

Mike Blissenbach

Mike Blissenbach

Analysis of Protein Changes Associated With Photosynthetic Recovery in Winter Stressed Conifers.

Click here to read the entire abstract

 

 
 

 

  

 

 

Grant Applications and Awards
 

USDA NRI Seed Grant – fall 2004 through fall 2006

Bush Grant (Core Area Grant through University of St. Thomas) - summer 2003

University of St. Thomas Research Assistance Grant - summer, 2000

National Science Foundation graduate fellowship- fall 1993 - summer 1996

 

 

 

Student Researchers
 
Current Previous

  • Angela Osmolak

  • Kelly Braddock (George)

  • Mike Blissenbach

  • Jordan Crow

Jordan Crow

  • Paul Morales

  • Mike Tangen

  • Ritu Sachdeva

  • Michelle Hackner (Breck High School Student)

  • Laura Suurmeyer

  • Leigh Farrell

  • Margaret Broeren

  • Adam Yock (high school student form Breck High School)

  • John Whiteman

  • Andrea Swanberg

  • Mai Thao

  • Beth Brinda (high school student form Breck High School)

  • Niko Tsastos

  • Rob Thoms (student from Macalester college)

 

 
 


                                      

         

         

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