Daniel Hardy, Ph.D.
| Assistant Professor | daniel.hardy@ttuhsc.edu |
Biography
- B.S., Chemistry (ACS Certified), 1979, South Dakota School of Mines & Technology
- Ph.D., Biochemistry, 1986, University of New Mexico School of Medicine
- NIH Postdoctoral Trainee, 1986, University of California, Davis
- NRSA Postdoctoral Fellow, 1987, University of California, Davis
- HHMI Associate, 1989, Vanderbilt University School of Medicine
- 1990, University of Texas Southwestern Medical Center
- Assistant Instructor, 1992, University of Texas Southwestern Medical Center
- Assistant Professor, 1995, Texas Tech University Health Sciences Center
- Associate Professor, 2002, Texas Tech University Health Science Center
Awards and Honors
- Kenneth L. Knight Award (shared), Top Research Publication of 2002, National Athletic Trainers' Association
- Editorial Board Member, 2004- , The Journal of Biological Chemistry
- Chair of the Graduate Faculty, 2005-2006
- TTUHSC President's Award for Excellence in Teaching, 2006
- Member, American Society for Biochemistry & Molecular Biology
- Member, Orthopaedic Research Society
Research Interests
Molecular basis of fertilization in mammals
The union of sperm and egg to form a new individual is one of the most extraordinary and fascinating processes in biology. Fertilization must succeed for individuals to pass on their unique genetic complements, and thus for a species to thrive. We are studying the molecular mechanisms by which sperm cells find, recognize, and penetrate the egg, with an emphasis on the inter-species variation of proteins that mediate these events. This research led to the discovery of zonadhesin, a large sperm protein that binds in a species-specific manner to the egg's extracellular matrix (zona pellucida). The amino acid sequence and domain structure of zonadhesin vary markedly among animal species, which may explain the protein's species-specific binding activity. Current research projects include analysis of the biochemical basis of zonadhesin's interaction with the zona pellucida, comparison of zonadhesin polypeptides and binding activity in equine species (horse, zebra, donkey) that can successfully interbreed, and characterization of the fertilization phenotype of zonadhesin knockout mice. In addition, we are conducting a targeted proteomics study to identify new sperm proteins that mediate cellular events of fertilization. This research has been supported by a grant from the NIH (HD-35166) and is currently supported by a grant from the Texas Department of Agriculture.
- Olson GE, Winfrey VP, Bi M, Hardy DM, NagDas SK (2004) Zonadhesin assembly into the hamster sperm acrosomal matrix occurs by distinct targeting strategies during spermiogenesis and epididymal maturation. Biol Reprod 71, 1128-1134
- Bi M, Winfrey VP, Olson GE, Hardy DM (2003) Processing, localization, and binding activity of zonadhesin suggest a function in sperm adhesion to the zona pellucida during exocytosis of the acrosome. Biochem J 375, 477-488
- Hickox JR, Bi M, Hardy DM (2001). Heterogeneous processing and zona pellucida binding activity of pig zonadhesin. J Biol Chem 276, 41502-41509
- Wilson MD, Riemer C, Martindale DW, Schnupf P, Boright AP, Cheung TL, Hardy DM, Schwartz S, Scherer SW, Tsui L-C, Miller W, Koop BF (2001). Comparative analysis of the gene dense ACHE/TFR2 region on human chromosome 7q22 with the orthologous region on mouse chromosome 5. Nucleic Acids Res 29, 1352-1365
- Haden NP, Hickox JR, Whisnant CS, Hardy DM (2000) Systematic characterization of sperm-specific membrane proteins in swine. Biol Reprod 63, 1839-1847
- Hardy DM, Garbers DL (1995) A sperm membrane protein that binds in a species specific manner to the egg extracellular matrix is homologous to von Willebrand factor. J Biol Chem 270, 26025-26028
- Hardy DM, Garbers DL (1994) Species-specific binding of sperm proteins to the extracellular matrix (zona pellucida) of the egg. J Biol Chem 269, 19000-19004
- Hardy DM, Hedrick JL (1992) Oviductin. Purification and properties of the oviductal protease that processes the 43,000 Mr glycoprotein of the Xenopus laevis egg envelope. Biochemistry 31, 4466-4472
- Hardy DM, Oda MN, Friend DS, Huang TTF Jr (1991) A mechanism for differential release of acrosomal enzymes during the acrosome reaction. Biochem J 275, 759-766
- Hardy DM, Schoots AFM, Hedrick JL (1989) Caprine acrosin: Purification, characterization, and effects on the porcine zona pellucida. Biochem J 257, 447-453
Maintenance and repair of connective tissue in injury and aging
Connective tissues such as ligaments, tendons, and the discs of the spine undergo a continuous process of maintenance and repair that is essential for the health and structural integrity of the tissues. Turnover of the structural proteins in these tissues is a key component of connective tissue growth, maintenance, and repair. We are studying the basic molecular processes that control protein turnover in these tissues, with an emphasis on sex differences that may explain the increased susceptibility (3-8 times higher) of female athletes to injuries of the anterior cruciate ligament (ACL) of the knee as compared to males. Current projects include global and focused gene expression profiling in ACL to identify sex differences, to characterize their natural variation in the human population, and to determine the influence of sex hormones on them. We are also characterizing aging- and injury-associated changes in these processes in intervertebral discs to understand progression of disc degeneration, and in knee ligaments to understand progression of osteoarthritis. This research has been supported by grants from the Orthopaedics Research Society and is currently supported by a grant from the NIH (AR-049767).
- Slauterbeck JR, Hickox JR, Hardy DM (2007). Ligament biology and its relationship to injury forces. In: Understanding and preventing non-contact ACL injury (Hewett T, ed) American Orthopaedic Society for Sports Medicine (AOSSM), Rosemont IL in press
- Slauterbeck JR, Hickox JR, Beynnon B, Hardy DM (2006) Anterior cruciate ligament biology and its relationship to injury forces. Ortho Clin N Am 37, 585-591
- Slauterbeck JR, Pankratz K, Xu KT, Bozeman SC, Hardy DM (2004) Effects of ovariohysterectomy and orchiectomy on the prevalence of ACL injury in dogs. Clin Orthop 429, 301-305
- Slauterbeck JR, Fuzie S, Smith MP, Clark RJ, Xu KT, Hardy DM (2002) The menstrual cycle, sex hormones, and anterior cruciate ligament injury. J Athletic Training 37, 275-280
- Foos MJ, Hickox JR, Mansour PG, Slauterbeck JR, Hardy DM (2001). Expression of matrix metalloproteinase and tissue inhibitor of metalloproteinase genes in human anterior cruciate ligament. J Orthop Res 19, 642-649
- Slauterbeck JR, Hardy DM (2001) Sex hormones and knee ligament injuries in females. Am J Med Sci, 322, 196-199