Title: The Role of Ccn1 in Tendon Development and Maintenance
Josephine Hai is a fourth year majoring in Molecular, Cell, and Developmental Biology. She joined the Lyons Lab in the beginning of her third year, and is currently investigating the role of CCN1/Cysteine-rich angiogenic inducer 61(Cyr61) in tendon development and maintenance.
Tendons are one of the major types of tissue of the musculoskeletal system, along with cartilage, ligament, muscle, and bone. They consist mostly of collagen fibrils tightly
bundled into fibers, an arrangement which gives them their characteristic mechanical
stability in anchoring muscle to bone. Although tendons are essential to movement, their development is the least understood of all musculoskeletal tissues, impeding research on repair strategies.
To address this gap in knowledge, we have focused on the matricellular protein CCN1, already known for promoting angiogenesis, cell differentiation, and cellular senescence. When knocked out in mouse limbs, we discovered mutants exhibiting a clubfoot phenotype and waddling gait. Upon closer examination, their Achilles and patellar tendons appeared significantly thicker and denser than those of their wild-type littermates, a unique phenotype which has not yet been described in any other mutant to date. By further studying this interesting phenotype, Josephine hopes to gain a better understanding of normal tendon development, which may then lead to very necessary novel approaches to tendon repair.
Josephine would like to thank Dr. Karen Lyons for the special opportunity of conducting research in her lab, Drs. Jie Jiang and Weiguang Wang for their invaluable training and mentorship, and all the undergraduate and graduate lab members for their help and advice. Additionally, she would like to thank the URC-Sciences staff members for their constant guidance and the Arnold and Mabel Beckman Foundation for its generosity in supporting her research endeavors.
Tim works in Dr. Hanna Mikkola’s lab, researching how blood stem cells (the cells that give rise to all the many different kinds of blood cells) arise during early human development and are maintained throughout our lives. There are a huge number of factors that play into these processes, and understanding them is critical to developing treatments for blood disorders.
Tim became interested in a science career during high school when he visited a research laboratory studying infectious diseases. At UCLA, he started doing research as a freshman in Dr. Vatakis’s lab, studying neonatal HIV infections and treatment strategies. Eventually, he started working with blood stem cells (also known as hematopoietic stem cells), which led to his transitioning into Dr. Mikkola’s lab. After graduation Tim will be starting the NIH Postbac IRTA (Intramural Research Training Award) program before starting his graduate studies.