John PlenefischAssociate Dean, College of Natural Sciences and Mathematics
Ph.D., Massachusetts Institute of Technology (M.I.T.), 1990
Office: WO 2246
Phone No: 419.530.7840
Lab: WO 3256
Phone No.: 419-530-1547
In my research laboratory I study the contribution of intermediate filaments to mechanical stress resistance in the epidermis of the nematode Caenorhabditis elegans as a general model for understanding how these proteins contribute to reinforcing cells and tissues against mechanical forces in other animals and in humans. These proteins are crucial for maintaning cellular and organismal integrity and the transmission of mechanical force between adjacent tissues.
Every living organism has a characteristic form. In simple unicellular organisms such as bacteria or yeast this form is the same as the form of the cell. In multicellular organisms such as worms or ourselves this form emerges from the shape of individual cells and the geometry of their assembly into a mechanically coupled structure. The coupling of cells together depends on the formation of attachments between adjacent cells, or between cells and surrounding non-cellular matrices during development and also depends on the linkage of these attachments to stress resistant cytoskeltal networks. In my lab we study the formation and maintenance of cell attachments between the epidermis and surrounding tissues and in particular the contribution of intermediate filaments to this process. Normal locomotion in this simple invertebrate requires transmission of contractile force from the skeletal muscles to the exoskeleton (cuticle) via a series of cell-matrix and cell-cell attachments, mediated by intermediate filament conncetions in the epidermis.
In C. elegans, the cytoplasmic IF proteins IFA-2, IFA-3, IFB-1 and IFC-1 are expressed in the epidermis, where they contribute to the mechanical connections that transmit the force of skeletal muscle contraction to the cuticle. We have shown that IFA-2 is likely to directly interacts with hemidesmosome attachment structures, as do IFA-3 and IFB-1. We have also defined the specific domains of IFA-2 that interact with these structures, and are currently examining IFA-3 and IFC-1 to understand the developmental dynamics of their expression, and their specific roles in maintaining epidermal integrity and hemidesmosome structure.
Williams, K., K. Williams, H. Baucher, and J. Plenefisch (2015) The Tail Domain Is Essential but the Head Domain Dispensable for C. elegans Intermediate Filament IFA-2 Function Plos One 0(3): e0119282.
Xiao, H.; V. Hapiak; K. Smith, L. Lin; R. Hobson, J. Plenefisch; R. Komuniecki, (2006) SER-1, a Caenorhabditis elegans 5-HT(2)-like receptor, and a multi-PDZ domain containing protein (MPZ-1) interact in vulval muscle to facilitate serotonin-stimulated egg-laying. Dev. Biol. 298:379-91
V.Hapiak, M. C. Hresko, L. A, Schriefer, K. Saiyasisongkhram, M. Bercher and J. Plenefisch (2003) mua-6, a Gene Required for Tissue Integrity in C. elegans, Encodes a Cytoplasmic Intermediate Filament Dev. Biol. 263:330-342
Bercher, M, J. Wahl, B. E. Vogel, C. Lu, E. M. Hedgecock, D.H.Hall, and J.D. Plenefisch (2001) mua-3, a gene required for mechanical tissue integrity in Caenorhabditis elegans, encodes a novel transmembrane protein of epithelial attachment complexes J. Cell. Biol. 154:415-426
Geng J, Plenefisch J, Komuniecki PR, Komuniecki R. (2002) Secretion of a novel developmentally regulated chitinase (family 19 glycosyl hydrolase) into the perivitelline fluid of the parasitic nematode, Ascaris suum. Mol Biochem Parasitol. 124:11-21.
Hapiak, V, M. C. Hresko, L. A. Schriefer, K. Saiyasisongkhram, M. Bercher and J. Plenefisch (2003) mua-6, a Gene Required for Tissue Integrity in Caenorhabditis elegans, Encodes a Cytoplasmic Intermediate Filament. Dev. Biol. 263:330-342
Plenefisch, J.D. , X. Zhu, and E. M. Hedgecock (2000) Fragile Skeletal Muscle Attachments in Dystrophic Mutants of Caenorhabditis elegans: Isolation and Characterization of the mua Genes Development 127, 1197-1207
Plenefisch, J., H. Xiao, B. Mei, J. Geng, P. R. Komunieki, R. Komunieki (2000) Secretion of a novel class of iFABPs in Nematodes: coordinate use of the Ascaris/Caenorhabditis model systems. Molec. Bioch. Parasit. 105, 223-236
H.Hutter, B. E. Vogel, J. D. Plenefisch, C. R. Norris, R. B. Proenca, J. Spieth, C. Guo, S. Mastwal, X. Zhu, J. Scheel, and E. M. Hedgecock (2000) Conservation and Novelty in the Evolution of Cell Adhesion and Extracellular Matrix Genes. Science 287, 989-994