Denver Baptiste

Our food supply is affected by insufficient produce, even under the most favorable environmental conditions. This problem is compounded by arid and high salinity regions. To find a solution, my research analyzes the genome and protein- protein interactions of Arabidopsis thaliana (A. thaliana) under unfavorable growth conditions to understand the interactions in plants that regulate or are regulated by environmental stress conditions. If
we know which molecular factors are affected by stressful conditions in plants, we can increase yield to alleviate growing hunger around the world to a population that is
increasingly demanding more food; even when conditions may not naturally be favorable to produce a variety of crop in environments we may think of as barren waste lands due to drought or nutrient deficiency. One of the mechanisms that are known to be associated with affecting plant development in environmental stress conditions is the Receptor for Activated C Kinase 1 (RACK1) protein.

RACK1 is a scaffold protein with three genes (RACK1A, RACK1B and RACK1C) that is ubiquitously expressed in Eukaryotic organisms. This protein contains 40 repeats of tryptophan-aspartic acid and bridge the interaction of its binding partners, integrating cellular signals to control transcription, translation and as a result regulates plant growth and development. Its association with signaling affects growth in drought and salt stress, growth hormones, innate immunity, and sugar distribution in plants. RACK1 has been shown to affect the global accumulation of miRNA and as a result plant hormones abscisic acid (ABA) and auxin. miRNAs are single stranded non-coding RNAs that serve
as gene regulators in a wide range of organisms. ABA and auxin are plant phyto-hormones. RACK1 negatively regulates the stress hormone ABA pathway and is known to positively regulate auxin. An array of miRNAs regulates the ABA stress mediated
drought signaling pathways. I have shown that RACK1 induction of miR393 (miR393A and miR393B) signaling down regulates auxin and as a result A. thaliana acclimation to salt stress.

My research with students will therefore further elucidate the implication of the proposed interactions of RACK1 with miRNAs and their effects on ABA and auxin in plant growth and development. We will analyze the role of RACK1-miR393 pathway in regulation of plant hormones ABA and auxin. This interaction will be elucidated using single and double mutants of RACK1 and miR393 in various environmental stress conditions such as drought and salt. Our mutations will make use of mendelian crosses and CRISPR/Cas9 techniques.

We will apply genome and protein analysis to make conclusions to support what we see phenotypically (germination, root growth, guard cells and chlorophyll accumulation in leaves).

Understanding the precise molecular mechanism of drought stress signaling and nutrient deficiency mediated by the interaction of RACK1, miRNA and plant phytohormones ABA and auxin will allow developing engineered crops better suited to withstand
stressful conditions.

-Judge for NAACP Afro-Academic, Cultural, Technological and Scientific Olympics (2022)

-Tri Beta Biological Honor Society Keynote Speaker (2021)

-Judge for Metropolitan Association of College and University Biologists (MACUB) Conference (2020)

-Presentation: Denver Jn. Baptiste, Sushma Mannimala, Thejasvi Venkatachalam, Karla Larios and Martha Soto (2020)
The Allied Genetics Conference (TAGC) 2020
“Which GEF activates Rac1/CED-10 during epidermal morphogenesis?”

-Presentation: Denver Jn. Baptiste and Martha Soto “How cells move and molecules that help these cells move” (2020)
INSPIRE Teaching Presentation

- Assistant Professor- Biology Department (Saint Peter's University)

- Postdoctoral Fellow- Robert Wood Johnson Medical School (Molecular Genetics), Rutgers University

- Adjunct Instructor- (Biology Department) Chattanooga State University

- Just Julian Graduate Research Grant 2019
- American Society of Plant Biologists (ASPB) Travel Grant 2018
- Alliance for Graduate Education and Professoriate Fellowship 2016 (AGEP)
- American Society of Plant Biologists (ASPB) Travel Grant 2016

Physiology, Biotechnology, Cellular Molecular Biology,
Bioethics, Ecology and Evolution, General Biology