Dr. Mannie Liscum

Mannie Liscum
Professor of Biological Sciences
108 Tucker Hall

PhD, 1992 Ohio State University

Research Summary

Genetic control of phototropism in plants

Research Description

All living organisms utilize both exogenous and endogenous cues to regulate their metabolism, growth and development. Plants, given their ‘fixed in the ground’ (sessile) nature are especially sensitive and responsive to their environment and exhibit highly plastic developmental programs. Unlike animals where the body plan is established almost entirely during embryogenesis, plant form and function is mostly elaborated post-embryonically. This dominance of post-embryonic patterning and growth affords plants the plasticity they need to modify their growth, morphology and behavior to even subtle and rapid changes in their environment. Because environmental inputs are numerous and ever changing, responsiveness of an organism is highly integrated, where multiple input signals are ‘sorted’ and transduced in an efficient manner to give rise to proper adaptive responses. Our laboratory is interested in how light acts as an environmental regulator of such integrated signal-response systems from molecules to functional ecology, and employ Arabidopsis thaliana as a model for most of our studies.

Though our laboratory has historically focused on phototropism as a model response, we have recently changed focus to examine the role of light in the modulation of reactive oxygen species (ROS) production and signaling. We are working to elucidate the molecule mechanisms by which phytochrome B (phyB), one of the five red/far-red photoreceptors in Arabidopsis, is integrated into the ROS responses to a variety of stress. Two elements of the ROS stress responses are of particular interest: 

  1. How does cytoplasmic-localized phyB regulate the rapid production of ROS via plasma membrane-localized NADPH-oxidases (respiratory burst oxidase homolog, RBOH; termed NOX in animals)? 
  2. How does nuclear-localized phyB regulate the long-term adaptation response that requires altered patterns of gene expression, and allows the plant to withstand exposure to subsequent stresses? 

We are tackling these questions in collaboration with Profs. Ron Mittler (Division of Plant Sciences), Yosef Fitchman (Tel Aviv University), and Johanna Morrow (Westminster College; and Mizzou Biology PhD).

Beyond his interests in light-regulated plant growth and development, Prof. Liscum is also interested in how prejudice has impacted, and still impacts, science and public policies of exclusion and worse. Much of this interest is currently focused on eugenics, past and present; a topic central to an Honors course Prof. Liscum co-teaches with another DBS faculty member, Prof. Michael Garcia. As a faculty scholar in the Middleton Center for Race, Citizenship & Justice, Prof. Liscum is also working with other Mizzou faculty from diverse disciplines to ask: 

  1. How is/was science, both historically and contemporarily, influenced by concepts of race, ethnicity, and prejudice? 
  2. How do such influences impact the societal and ethical outcomes of scientific study?
Awards and Honors

Writing Intensive Teaching Excellence Award 2022

David B. Dunn Faculty Award in Plant Biology 2020

Phi Kappa Phi National Honor Society 2015

Rollins Society Inductee 2014

Outstanding Director of Graduate Studies, MU 2007

Fellow, American Association for the Advancement of Science 2004

New Investigator Award, American Society for Photobiology 2000

Selected Publications

See Google Scholar for a list of Dr. Liscum's publications.