Perisotin-like-factor (PLF) is a member of the Fasciclin family of proteins, which are characterized by the presence of 150 amino acid long conserved Fasciclin domains. Members of this family have been implicated in numerous cellular processes like adhesion, migration, axonal guidance and growth cone extension. PLF plays an important role during embryonic development, however very low levels are present in adults. PLF is up regulated in adult tissues when they are exposed to stress or insult. We have previously shown that PLF is up regulated in heart when they are mechanically overloaded and in lung when exposed to cigarette smoke. Similarly in bone, PLF is highly up regulated in fractured bone calli, albeit not present in normal adult bone. Furthermore PLF leads to increased bone formation in vivo in the bone marrow cavity when over expressed adenovirally. These results suggest that PLF promotes tissue repair and healing after injury. Additionally, PLF expression was up regulated in musculoskeletal tissues in our innovative model of Upper extremity-Work Related Musculoskeletal Disorder (WMSD). In this model, which draws parallels between the exposure to risk factors and development of associated disorders in human PLF was expressed in bone, skeletal muscle, tendon and nerves. Coincidentally, these are the same tissues in which PLF is expressed during embryonic development. Additionally, PLF was detected in inflammatory cells like macrophages suggesting a role for PLF in inflammation. Molecules like PLF which play important roles during development, reappear when the tissues require them, promoting their remodeling and recovery can be targeted as therapeutic agents. Such molecules can be targeted after injury or disease. In this study we focus our attention on the role of PLF in musculoskeletal (muscle and bone) remodeling in our animal model of WMSD. / Anatomy