Mandy Kendrick
Advised by Dr. Caren Chang, Associate Professor
PhD Candidate, Department of Cell Biology and Molecular Genetics
From: Missouri
Education/work:

• Bachelor of Science in Plant Science from the University of Missouri
• Worked as a research intern with Monsanto in herbicide development

Interesting Fact: She could drive a tractor by the age of 6 and had a pet calf named Red.

Mandy Kendrick, who grew up on a farm, had always thought plants were boring and had planned on pursuing veterinary medicine.  All this changed when one day her biology teacher in college mentioned how plants turn yellow when they are deprived of nitrogen.  This interesting bit of information got Mandy thinking about plants’ molecular mechanisms and the need to react rapidly to changes in environment.

Pursuing Her Newfound Passion For Plants

As a PhD student, Mandy works in Dr. Caren Chang’s lab on the Arabidopsis weed, which serves as a model organism for plants with more complex genomes.  The lab studies the gaseous plant hormone ethylene and is particularly interested in understanding the molecular switches behind ethylene signaling, from the time point that ethylene is produced and perceived by the plant’s ethylene receptors to ethylene-induced responses, such as fruit ripening or flower petal senescence.

By testing for protein-protein interactions in yeast, Chang’s lab previously identified many Arabidopsis proteins that could be involved in ethylene signaling based on each protein’s ability to directly interact with the Arabidopsis ethylene receptor protein ETR1.  One of these proteins EIP1 (ETR1-Interacting Protein1) is of special interest because it can also associate with additional proteins known to be involved in ethylene signaling.

Figuring out the Role a Protein Plays in a Cell

Mandy’s work focuses on characterizing EIP1 and trying to elucidate its function. This protein is particularly interesting to her because the sequence of EIP1 has no conserved or well characterized domains to aid in the understanding of its function. Through phenotypic analysis of an eip1 mutant, Mandy found that themutant seedlings are shorter than wild type and the adult plants have smaller, more compact leaves than wild type. After taking a closer look at the eip1 epidermal cells Mandy suggests that the smaller, more compact phenotype is a consequence of smaller cells.   This finding indicates that EIP1 may play a role of in cell elongation, a process that requires both ethylene-dependent as well as ethylene-independent signaling pathways. 

In order to confirm this phenotype, Mandy will attempt to reduce the expression of EIP1 in wild-type plants, using a new technology available to Arabidopsis researchers, called amiRNA (artificial microRNA’s) which target specific RNA’s (in my case the EIP1 mRNA) for degradation.  If reducing EIP1 expression results in the same smaller, more compact phenotype as the previously mentioned eip1 mutant, then her proposed hypothesis that EIP1 is involved in cell elongation is strengthened.  In addition, Mandy has analyzed plants that over-express EIP1.

Interestingly, over-expression of EIP1 can rescue the small, compact phenotype seen in the eip1 mutant.  By further analyzing the affects of over-expressing EIP1 in plants that are mutated in ethylene signaling, she found that EIP1 seems to require the ethylene receptor ETR1 for proper function.  By visualizing fluorescent markers using the department’s Zeiss LSM510 confocal microscope, Mandy hopes to confirm that EIP1 and ETR1 can interact in plants, similarly to what was initially found in yeast.   Collectively the information and data Mandy is generating should help the research community decipher how EIP1 is functioning in cell elongation.

Why UMD was the Perfect Fit, and Future Steps

Mandy wanted to attend UMD because she felt like it had a strong core of people and was made up by a very interesting community.  In addition she appreciated the genuine and helpful interactions she had with the graduate director.  The geographic location, nice diversity and topnotch lab tools provided added bonuses. Mandy will be graduating from UMD in December 2008 and is looking forward to either pursuing a post-doc position, possibly in plant pathology, or perhaps going into science education.

Visit Dr. Chang's Lab website for more information on Mandy's research.

Visit the Department of Cell Biology and Molecular Genetics website.