Faculty/Staff Directory

Margaret Dietrich

Email
dietrima@gvsu.edu

Title
Associate Professor

Office Address
3349 Kindschi Hall of Science

Office Phone
616-331-2816

Areas of Expertise
Plant Signaling and Development

Courses Taught at GVSU

BIO 120 General Biology (lecture)
BIO 403 Plant Structure and Function (lecture and laboratory)
BIO 423 Plant Development and Biotechnology
CMB 150 Biotechnology and Society (lecture and laboratory)
CMB 250 Introduction to Biotechnology
CMB 405 Cell and Molecular Biology Lecture
CMB 406 Cell and Molecular Biology Laboratory
CMB 426 Nucleic Acids Laboratory
CMB 501 Scientific Communication
CMB 626 Advanced Nucleic Acids Laboratory

Research Interests

Plant development, signal transduction in plants

My research interests are focused in the areas of plant physiology and development. I am particularly interested in how a plant perceives a signal, whether physiological (like a hormone) or environmental, and how such perception leads to altered growth and development. Being literally rooted in place, plants must respond to such signals quickly and appropriately if they are to survive and reproduce.

My primary project involves tip growth, the type of growth that underlies 1) the formation of root hairs, which are responsible for water and nutrient uptake into ‘higher’ plants from the soil, and 2) pollen tube growth, the mechanism by which the sperm nuclei reach the embryo sac in flowering plants to result in fertilization. Both are crucial to plant success and, therefore, are crucial to animals, including humans, which rely on plants as food and oxygen sources. As such, they are integral to the production of agricultural crops and, therefore, food security.

I use the moss, Physcomitrella patens, as a model system for investigating tip growth as the moss grows exclusively via tip growth for a portion of its lifecycle, can be grown in culture (and so the environment can be manipulated), and is easily viewed under the microscope. We are currently characterizing an interesting random insertional moss mutant which exhibits some aberration in tip growth.

A number of GVSU undergraduate students have worked with this mutant so that we now know: a) that the site and possibly the rate of growth of newly established tip growth are affected by the disruption of the genome, b) the location in the genome that was disrupted when the mutant was made, c) that it appears sequence directly encoding a protein was not disrupted at this site in the mutant (suggesting that some type of regulatory sequence/function was disrupted instead), and d) that there are repeated DNA sequence elements present at the site of the disruption in the genome.

We are currently working toward addressing two questions:

 • How is gene expression different in the mutant as compared to the normal moss?  We are using an RNA-seq approach to this question to look at differential gene expression. This will generate a huge amount of data in the form of short ‘reads’ from the cDNAs, which then must be assembled computationally before we can compare the transcript populations from the normal and mutant moss, again using computational biology. This is a ‘big data’ project. 

• By what mechanism might the repeated sequences be regulating gene expression in the normal moss?  The disrupted locus contains repeated retrotransposon sequence as well as a stretch of 11 bp tandem repeats (approximately half of which were deleted when the mutant was made). A number of miRNAs are predicted to be produced from this locus and we will be using 5’RACE to detect the primary transcript (which is then processed to produce the functional miRNAs themselves) in the normal moss.

This project has involved the use of multiple approaches: genetic, cellular, molecular, and biochemical. In addition, given the direction of the moss project, computational biology will be added to the list.

In addition, I have had several collaborative projects with Dr. Gary Greer (BIO) in the past.

Education

Ph.D. in Plant Physiology with a Supporting Program in Biochemistry and Genetics, University of Minnesota-Twin Cities
B.S. in Biochemistry, University of Wisconsin-Madison, with distinction
Postdoctoral Fellow, University of Arizona
Sabbatical (2009-2010), University of Arizona

Select Publications

Greer, G.K., Dietrich, M.A., and J.M. Lincoln*. 2016. Ailanthus altissima stimulates legume nodulation via root exudates: a novel mechanism facilitating invasion? Int. J. Plant Sci. 177(5):400-408.

Greer, G., Dietrich, M.A., DeVol*, J., and A. Rebert*. 2012. The effects of exogenous cytokinin on the morphology and gender of Osmunda regalis gametophytes. Am. Fern J. 102 (1): 32-46.

Greer, G.K., Dietrich, M.A., Stewart* S., DeVol*, J., and A. Rebert*. 2009. Morphological functions of endogenous gibberellins in filicalean gametophytes: insights into the evolution of form and gender expression. Bot.  J. Linn. Soc. 159:599-615.

Recent Presentations

Freiman*, A. and M.A. Dietrich. Abnormal growth patterns of a P. patens mutant phenotype may be due to disrupted miRNAs. Poster presentation at the West Michigan Regional Undergraduate Science Research Conference, Grand Rapids MI, 11/17.

Freiman*, A. and M.A. Dietrich. miRNAs derived from retrotransposon sequences may be responsible for a P. patens mutant phenotype. Poster presentation at the West Michigan Regional Undergraduate Science Research Conference, Grand Rapids MI, 11/16.

Prieskorn*, B. and M.A. Dietrich. A disruption in repeated sequence may be responsible for a P. patens mutant phenotype. Poster presentation at the West Michigan Regional Undergraduate Science Research Conference, Grand Rapids MI, 11/15.

Kamgang*, R. and M.A. Dietrich. Assessment of polar growth of a Physcomitrella patens insertional mutant. Poster presentation at the West Michigan Regional Undergraduate Science Research Conference, Grand Rapids MI, 11/14.

Dietrich, M.A., R. Kamgang*, and E. Morrison*. Defective apical growth, timing of initiation of polar growth, and hormone response in a Physcomitrella patens insertional mutant. Poster presentation at the national conference of the American Society of Plant Biologists, Portland OR, 7/14.

Morrison*, E. and M.A. Dietrich. Atypical apical growth, timing and hormone response in a Physcomitrella patens developmental mutant. Poster presentation at the West Michigan Regional Undergraduate Science Research Conference, Grand Rapids MI, 11/13.

Roth*, M. and M.A. Dietrich. The role of CBL10 in stamen development in Arabidopsis thaliana. Poster presentation at the West Michigan Regional Undergraduate Science Research Conference, Grand Rapids MI, 11/13.

Marmion*, R. and M.A. Dietrich. Abnormal initial cell formation in Physcomitrella patens. Poster presentation at the West Michigan Regional Undergraduate Science Research Conference, Grand Rapids MI, 11/12.

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