Harold Paul Erickson (Secondary)
Gene Function and Regulation, Protein Structure, Structural Biology.
For the latest information on the Erickson Lab, please visit our website.
Nanaline Duke, Room 412, Box 3709, Durham, NC 27710
Cytoskeleton: It is now clear that the actin and microtubule cytoskeleton originated in bacteria. Our major research is on FtsZ, the bacterial tubulin homolog, which assembles into a contractile ring that divides the bacterium. We have studied FtsZ assembly in vitro, and found that it assembles into thin protofilaments. Dozens of these protofilaments are further clustered to form the contractile Z-ring in vivo. Recent discoveries include:
- The Z ring is very dynamic, exchanging subunits with a half time of 8 s.
- Reconstitution of Z rings in vitro. We provided FtsZ with a membrane tether, and found that when incorporated inside liposomes, membrane-targeted FtsZ can assemble Z rings without any other proteins.
- These reconstituted Z rings can also generate a constriction force on the membranes, again without any other proteins (no motor molecules).
- The constriction force is generated by a curved conformation of the protofilaments generating a bending force on the membrane.
- Negative stain EM of artificial Z rings shows ribbons of protofilaments, contradicting the prevailing view from cryoEM tomography of scattered protofilaments
Our long term goals are two-fold. First, to understand the mechanism of bacterial cell division. Second, to learn basic principles of assembly and mechanics that will apply to both FtsZ and tubulin.
Extracellular Matrix: A second interest of our lab is extracellular matrix and cell adhesion, focusing now on fibronectin. We have discovered that the FN matrix is very elastic, with fibrils stretching up to four-fold over their relaxed length. We have two possible mechanisms to explain the elasticity of FN, and are currently developing experimental tests to resolve the mechanism. We are also studying the molecular structure of FN matrix fibrils and the mechanism of assembly. Assembly of "super FN" is providing important new insights.
- Structure and Assembly Dynamics of FtsZ awarded by National Institutes of Health 2014 - 2018
- Extracellular Matrix and Cell Attachment Proteins awarded by National Institutes of Health2012 - 2017
- Assembly, Dynamics and Regulation of Chloroplast FtsZ awarded by Michigan State University2011 - 2015
- Structure and Assembly Dynamics of FtsZ awarded by National Institutes of Health 2002 - 2014
- A Genomic and Structural Study of FTsZ Constriction in Cell Divison awarded by National Institutes of Health 2010 - 2013
- Extracellular Matrix and Cell Attachment Proteins awarded by National Institutes of Health2006 - 2012
- A Fluorescence-Based Biosensor for Measurement of Cell Derived Forces awarded by National Institutes of Health 2009 - 2011
- Graduate training in Biologically Inspired Materials awarded by National Science Foundation2002 - 2007
- Zeiss LSM510 META confocal-fluorescence spectroscopy awarded by National Institutes of Health2003 - 2004
- Development and Construction of Single Molecule Spectrometers for Research and Student Training awarded by National Science Foundation 2001 - 2003
- Structure and Assembly of Cytoskeletal Filaments awarded by National Institutes of Health1981 - 2002
- Center for FEL Research in the Medical, Biological, and Materials Sciences awarded by Air Force Office of Scientific Research 2000 - 2001
- Multivalent Ligands To Enhance Cell Receptor Binding awarded by National Institutes of Health1999 - 2000
- Structure & Assembly Of Cytoskeletal Filaments awarded by National Institutes of Health 1981 - 1999
- Tenascin Regulation Of Cell-Matrix Interactions In Skin awarded by National Institutes of Health1996 - 1997
- Tenascin Regulation Of Cell Matrix Interactions In Skin awarded by National Institutes of Health1995 - 1997
- Extracellular Matrix And Cell Attachment Proteins awarded by National Institutes of Health1996 - 1997
- Structure And Assembly Of Cytoskeletal Filamients awarded by National Institutes of Health1986 - 1989
- Electron Microscopy Of Plasma And Cell Surface Proteins awarded by National Institutes of Health1986 - 1988
- Electron Microscopy Of Plasma And Cell Surface Protein awarded by National Institutes of Health1986 - 1987
- 434uisition Of Philips Em 420 Microscope With Goniometer awarded by National Science Foundation1984 - 1985
- Phailips Em420 Microscope With Goniometer & Cryo Stage awarded by National Institutes of Health1984
PhD Johns Hopkins University, 1968