N [3]. Deepened understanding of the TGF-b signal transduction pathway has led increasing investigators to attempt at the inhibition of TGF-b transduction at various levels. Examples of these therapies include treatment with TGF-b antagonists [4], truncated TGF-b1 receptors [5], compounds capable of blocking the Smad3 signaling pathway [6], induced overMK 8931 custom synthesis expression of Smad7 [7], and gluco-Effects of TLP on Synthesis of Collagenscorticoids that block intranuclear signals [8]. Though these therapies all have exhibited some degree of definite efficacy, each is inevitably influencing biological effects of other signaling pathways. Some therapies have even been shown to be adverse to wound healing, such as overinhibition of the fibronectin synthesis. These effects have been puzzling investigators over the past decades by suggesting the existence of an undetermined target protein possessing specific and important biological effects on signaling pathways. Efficient and specific downregulation of such a protein could play a significant role in the expression of its downstream signals, thus affecting wound healing and scar formation. TRAP-1-like protein (TLP), an intermediate protein in TGF-b signaling pathway, is a novel human cytoplasmic protein recently separated and characterized. TRAP-1 is a specific molecular chaperone for Smad4, which brings Smad4 into the vicinity of the receptor complex and facilitates its transfer to the receptoractivated Smad proteins [9]. As a homologue of TRAP-1 with approximately 25 homology, it has been named as TRAP-1-like Protein (TLP), and it is also known as hVPS39 (human vacuolar sorting protein39) and hVam6p(human vesicle associated membrane protein 6). TLP has been found to be associated with the TGF-b/Smad signaling transduction pathway in addition to as a regulator in the transduction pathway, though its most significant role is likely its ability to regulate Smad2/3 in opposite directions simultaneously. Overexpression of TLP suppresses the expression of the Smad3/4 specific receptor protein (SBE) induced by TGF?b. Conversely, abundant TLP may strengthen the expression of the Smad2/4 specific receptor activin response element (ARE) [10]. TLP, a newly discovered molecule with high biological value, still remains unclear as to its relationship with the TGF-b/Smad signal transduction pathway and its role in fibrosis. This study probed into the problem of how TLP affected 18325633 the TGF-b/Smad signaling pathway, including its effects on the downstream signals and on collagen synthesis, with a view to providing attractive therapeutic targets to interfere with TGF-b signaling in wound healing and preventing hypertrophic scar SPDB web formation processes.293TN cells (ATCC, USA)to produce lentiviral vectors by transfection reagent Lipofectmine 2000, and the virus titer was analyzed with the gradient dilution method.Cell Culture and TransfectionExperimental samples were collected from patients undergoing operations in the Department of Plastic Surgery, Ninth People’s Hospital affiliated to Shanghai Jiao Tong University School of Medicine. As previously described [12], fibroblasts were obtained from normal human skin after enzymatic digestion. Skin tissue was cut into 0.5 cm3 pieces and the epidermis and dermis were isolated by digestion with 0.25 g/l Dispase II. The dermal tissue was minced and digested thoroughly with 30 volumes of 200 U/ ml collagenase I solution at 37uC for 2 hours. Then cells were collected by centrifugation.N [3]. Deepened understanding of the TGF-b signal transduction pathway has led increasing investigators to attempt at the inhibition of TGF-b transduction at various levels. Examples of these therapies include treatment with TGF-b antagonists [4], truncated TGF-b1 receptors [5], compounds capable of blocking the Smad3 signaling pathway [6], induced overexpression of Smad7 [7], and gluco-Effects of TLP on Synthesis of Collagenscorticoids that block intranuclear signals [8]. Though these therapies all have exhibited some degree of definite efficacy, each is inevitably influencing biological effects of other signaling pathways. Some therapies have even been shown to be adverse to wound healing, such as overinhibition of the fibronectin synthesis. These effects have been puzzling investigators over the past decades by suggesting the existence of an undetermined target protein possessing specific and important biological effects on signaling pathways. Efficient and specific downregulation of such a protein could play a significant role in the expression of its downstream signals, thus affecting wound healing and scar formation. TRAP-1-like protein (TLP), an intermediate protein in TGF-b signaling pathway, is a novel human cytoplasmic protein recently separated and characterized. TRAP-1 is a specific molecular chaperone for Smad4, which brings Smad4 into the vicinity of the receptor complex and facilitates its transfer to the receptoractivated Smad proteins [9]. As a homologue of TRAP-1 with approximately 25 homology, it has been named as TRAP-1-like Protein (TLP), and it is also known as hVPS39 (human vacuolar sorting protein39) and hVam6p(human vesicle associated membrane protein 6). TLP has been found to be associated with the TGF-b/Smad signaling transduction pathway in addition to as a regulator in the transduction pathway, though its most significant role is likely its ability to regulate Smad2/3 in opposite directions simultaneously. Overexpression of TLP suppresses the expression of the Smad3/4 specific receptor protein (SBE) induced by TGF?b. Conversely, abundant TLP may strengthen the expression of the Smad2/4 specific receptor activin response element (ARE) [10]. TLP, a newly discovered molecule with high biological value, still remains unclear as to its relationship with the TGF-b/Smad signal transduction pathway and its role in fibrosis. This study probed into the problem of how TLP affected 18325633 the TGF-b/Smad signaling pathway, including its effects on the downstream signals and on collagen synthesis, with a view to providing attractive therapeutic targets to interfere with TGF-b signaling in wound healing and preventing hypertrophic scar formation processes.293TN cells (ATCC, USA)to produce lentiviral vectors by transfection reagent Lipofectmine 2000, and the virus titer was analyzed with the gradient dilution method.Cell Culture and TransfectionExperimental samples were collected from patients undergoing operations in the Department of Plastic Surgery, Ninth People’s Hospital affiliated to Shanghai Jiao Tong University School of Medicine. As previously described [12], fibroblasts were obtained from normal human skin after enzymatic digestion. Skin tissue was cut into 0.5 cm3 pieces and the epidermis and dermis were isolated by digestion with 0.25 g/l Dispase II. The dermal tissue was minced and digested thoroughly with 30 volumes of 200 U/ ml collagenase I solution at 37uC for 2 hours. Then cells were collected by centrifugation.