Patrick Curtis
Assistant Professor of Biology
Phone Number: (662)915-1911
Email: pdcurtis@olemiss.edu
http://olemiss.edu/depts/biology/people/faculty/curtis/index.php

Key Words: Complex Cellular Systems, Prokaryotic Development, Gene Conservation

Research Description: My lab is interested in how bacteria adapt, repurpose and integrate signaling pathways to create complex cellular systems, particularly those of prokaryotic development. The model developmental bacterium Caulobacter crescentus has a dimorphic life cycle where after division the two resulting daughter cells have differing life styles. One cell has a thin cellular extension called the stalk; this cell can immediately re-enter the replication cycle. The other cell has a flagellum and is motile (swarmer cell), but cannot replicate. The swarmer cell must differentiate into a stalked cell before it can initiate replication. C. crescentus utilizes multiple regulatory systems (including global, temporally-controlled, and spatially-regulated systems) to create morphological and intracellular signaling asymmetry during cell division, but the extent and function of these systems are not well understood. My lab aims to understand the mechanisms by which these systems function.

Projects:
Brevundimonas subvibrioides as a model organism A close relative of C. crescentus, Brevundimonas subvibrioides, has the same developmental life cycle and many of the same developmental signaling systems. However, mutational analysis indicates there are several key differences in developmental signaling mutants of each species. This project will analyze the differences in the mutants to understand the mechanistic reasons for the differences, and what that can tell us about the function of the developmental signaling systems in each organism.

Conservation of essential genes It is becoming increasing evident that whole or part of the C. crescentus developmental life style is conserved throughout the alpha subdivision of the proteobacteria. This result indicates that the developmental program was present in some form early in the evolutionary history of this subdivision. Because the developmental program is built into the life cycle, many aspects are essential to cell viability. I have initiated whole-genome level identification of essential genes for several organisms in the alphaproteobacteria using a combination of transposon mutagenesis and high-throughput DNA sequencing. This project will be a continuation of that research and will include essential gene analysis of more alphaproteobacteria as well as comparison of conserved essentiality. The aim of this project is to uncover new conserved developmental signaling systems, see how developmental signaling systems change evolutionarily, and explore the nature of essential genes in an evolutionary context.

Honors Theses:

Chong, Sarah (2017) Effects of Mutating CtrA-Binding Sites within the pile Promoter of Caulobacter Crescentus. (full text)