Long Lab

Fanxin Long, Ph.D

Professor of Medicine and Developmental Biology

Department of Orthopaedics Washington University

BJC - Institute of Health
11th floor - RM 11613
Phone: (314) 454-8795

Click here to visit the Mouse Genetic Models Core website.


Research Interests
The human skeleton is a metabolically active and multifunctional organ critical for overall health. Research in the Long Lab is focused on the development, homeostasis and regeneration of the mammalian skeleton. They are particularly interested in how adult mesenchymal stem cells (MSC) are maintained and directed to differentiate along different lineages (e.g., cartilage, bone and fat) during skeletal maintenance and regeneration. Related to this interest is how disruption of the normal regulation contributes to skeletal diseases such as osteoporosis and osteoarthritis, both of which increase with aging and diabetes. Another interest of the lab is to elucidate the source of stem and progenitor cells responsible for skeletal homeostasis and regeneration in vivo. An emerging theme in the lab is on the role of cellular metabolism in cell fate and function. Current projects include mechanistic and functional studies of various intercellular signals through a combination of molecular, biochemical and mouse genetic techniques. They hope that their research will lead to novel strategies to treat osteoporosis and osteoarthritis, and to improve fracture healing particularly in patients with diabetes.

As seen through a microscope, the leg bone of a normal mouse (left) makes considerably less new bone than a mouse that produces high levels of a signaling protein, WNT7B, that stimulates new bone growth (shown in pink on the right). The protein could become a target for new drugs to treat osteoporosis and other conditions related to bone loss. (Chen et al., PLoS Genetics, 2014)

Dr. Long completed his bachelor of science degree in cell biology from Peking University in Beijing, China. He then earned a master's degree in Molecular Biology from the University of California in Santa Barbara, California and a doctorate degree in Developmental Biology from Tufts University Medical School, in Boston, Massachusetts. Dr. Long previously served as an Assistant Professor of Medicine and Developmental Biology as well as an Associate Professor of Medicine at Washington University School of Medicine. Dr. Long currently serves as a Professor of Medicine and Developmental Biology in the department of Orthopaedic Surgery at Washington University School of Medicine.

Selected Publications

  • Karner CM and Long F et al (2015). Increased glutamine catabolism mediates bone anabolism in response to Wnt signaling. JCI 125, 551-62.
  • Shi Y and Long F et al (2015). Hedgehog signaling activates a positive feedback mechanism involving insulin-like growth factors to induce osteoblast differentiation. PNAS 112, 4678-83.
  • Chen J and Long F (2014). mTORC1 signaling critically controls mammalian skeletal growth through stimulation of protein synthesis. Development 141, 2848-54.
  • Regan JN and Long F et al (2014). Upregulation of glycolytic metabolism is required for hypoxia-inducible factor-1α-driven bone formation. PNAS 111, 8673-8.
  • Esen E and Long F (2013). WNT-LRP5 signaling induces Warburg effect through mTORC2 activation during osteoblast differentiation. Cell Metab 17, 745-55.
  • X Tu and Long F et al (2012). Physiological Notch signaling maintains bone homeostasis via RBPjk and Hey upstream of Nfatc1. PLoS Genet.;8(3):e1002577.