Regulation of Drosophila metabolism and body size by an Activin-like signaling network

Abstract

The TGF• superfamily comprises the largest set of polypeptide growth and differentiation factors found in Nature and they regulate a plethora of important biological processes in all animals.   An unanswered question in the field is why their exists such a diversity in ligands that signal through a much smaller set of related receptors and signal transduction components.  We have been addressing this question through the study of three Drosophila activin-like ligands and their roles in regulating metabolism and body size.  We find that these different Activin-like ligands, achieve tissue-specific responses through intricate agonist-antagonist interactions with different Type I receptor isoforms.  These studies provide insight into how a responding tissue can decode a complex mixture of related extracellular growth factor signals into a unique regulatory output.

Bio

Dr. O’Connor received his Bachelor of Sciences degree in biochemistry from Brown University in 1976.  After several years working outside of academia, he attended graduate school at Tufts University School of Medicine and complete his PhD in 1984.  His thesis work was carried out under the guidance of Dr. Michael Malamy and examined mechanisms of drug resistance transfer in bacteria.  His postdoctoral work with Welcome Bender at Harvard focused on understanding the regulation of homeotic gene expression.  In 1988 he joined the faculty at the University of California-Irvine.  It was while at Irvine that he became interested in mechanisms of cell-cell communication and focused  his research efforts on understanding the role of BMPs and associated factors in regulation of dorsal patterning in the early Drosophila embryo.  In 1996 he moved to the Department of Genetics, Cell Biology and Development (GCD) at the University of Minnesota as an HHMI Investigator and the holder of the Ordway professorship in Developmental Biology.  His research at Minnesota continues to explore the molecular mechanisms by which TGF-beta type factors regulate developmental and homeostatic processes in Drosophila including roles in metabolic and body size control, imaginal disc growth and NMJ function.  In addition, he initiated a new research direction with emphasis on determine the molecular mechanisms of neuroendocrine signaling that control of timing of steroid production and the initiation of insect metamorphosis.  In 2010 he left HHMI and became the GCD department Head, a position he continues to hold today.