Project description:PBS and Il-5 (22 pM) treated LLC and B16 cells were harvested after 24 hours, for comparison between: 1) PBS and IL-5 trerated LLC cells, and 2) btween LLC and B16 cells at baseline conditions.
Project description:B16-F10 malignant mouse melanoma cells have been frequently used as highly metastatic cells. Based on heterogenous cell surface expression of Met/HGF (hepatocyte growth factor) receptor in B16-F10 cells, the cells were divided into Met-low and Met-high cells by flow cytometry and these populations were subjected to microarray analysis. Met-low and Met-high cells showed different expression profiles in genes involved characteristics of tumors, including stem cell maintenance, pigmentation, and angiogenesis.
Project description:Cellular homeostasis is an outcome of complex interacting processes with nonlinear feedbacks that span spatiotemporal scales. Skin tanning is one such dynamic response that maintains genome integrity of epidermal cells. While pathways underlying hyperpigmentation cascade are recognized, negative feedback regulatory loops that can dampen the activated melanogenesis process are not completely understood. By designing a pigmentation oscillator, in this study we delineate the role of interferon gamma (IFN-γ) signaling in skin pigmentation homeostasis. IFN-γ signaling reversibly controls maturation of the key organelle melanosome by concerted regulation of several pigmentation genes. We show that this temporal effect is mediated through interferon regulatory factor-1 (IRF-1) independent of the central regulator microphthalmia-associated transcription factor (MITF). Chronic expression of IFN-γ in mouse and human skin shows hypopigmentation phenotype, further providing a strong support to the under-appreciated function of IFN-γ in skin pigmentation. Our studies thus reveal the hitherto missing link between immune system and pigmentation, which may have implications in depigmentary and malignant cutaneous disorders. there are 12 samples from two consecutive cycles of pigmentation oscillator, termed set 1 and set 2 analysis is performed wrt to day 0 of first cycle