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Signal Transducers &Activators of Transcription( STAT) Family:Role of Stat 3 in Skin Disorders ,[object Object],[object Object]
INTRODUCTION
Signal   transducers   and   activators   of   transcription )  Stat) Family ,[object Object],[object Object],[object Object]
NK-22 cell-secreted cytokines stimulate epithelial cells to proliferate, release IL-10 and activate STAT1 and STAT3.   M Cella   et al.   Nature  000, 1-4 (2008)
 
CYTOKINES, CYTOKINE RECEPTORS, ACTIVATED SIGNALING MOLECULES AND MAJOR BIOLOGICAL FUNCTIONS ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
 
STAT3 Activation ,[object Object],[object Object],[object Object]
Mechanism of Stat3 signaling ,[object Object]
[object Object]
Class IIB(3)(b) latent cytoplasmic factors These families not present in fungi or plants, hinting at an important evolutionary divergence leading to animals.
STATs - a signal responsive TF family ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Simple signalling pathway
REGULATION of Cell Signaling
The JAK-STAT signalling pathway ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Canonical JAK–STAT pathway ,[object Object],[object Object],[object Object],[object Object]
IFN-response: two variants ,[object Object],[object Object],[object Object],[object Object],[object Object]
IFN-response:  two variants
STAT-family members ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
STAT-members SH2 Y
STAT-STAT interaction occurs through reciprocal phospho-Tyr - SH2 interactions ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Y P Y P Y + Y
Dimerization via SH2-Tyr P Tyr P  from the left monomer SH2 from the right monomer
STAT-members SH2 Y
STATs - structure and function ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],GAS= TTN 5-6 AA ISRE= AGTTTN 3 TTTCC
STAT-STRUCTURE ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
3D ,[object Object]
Promoter recognition and selectivity ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Transactivation Domain(TAD) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Other functional domains ,[object Object]
Psoriasis
Psoriasis ,[object Object],[object Object]
Psoriasis Clinical Presentation
Psoriasis as an immune disorder
T-Cell in Psoriasis
Immunomodulator(Alefacet) effect on Psorasis Area Score Index(PASI)
ANTI –Tumor Necrosis Factor (TNF) in Psoriasis
 
 
[object Object]
 
Stat3 in keratinocytes(KC)
Prepsoriasis State
Prepsoriasis State
Immunopathology of Psoriasis
Stat3 links activated keratinocytes and immunocytes required for development of psoriasis   ,[object Object],[object Object],[object Object],[object Object],[object Object]
New Informations
 
Development of Psoriasis
Manipulation of Psorasis
Do Other Therapies Work Within This Framework? ,[object Object],[object Object]
 
Studies on Stat 3 in Psoriasis
Stat 3 in Psoriasis
 
 
New Prospectives &Directions
 
Tyrosine  kinases
The JAK-family of tyrosine kinases ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
The role of the kinases in the signalling pathway INF  -signalling INF  -signalling
The cytokine-receptor superfamily ,[object Object],[object Object],[object Object],[object Object]
The role of the kinases in the signalling pathway INF  -signalling INF  -signalling
Specificity in response ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Several signalling pathways linked ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Cross  Talks ,[object Object],[object Object],[object Object],[object Object],P P P P P P P P JAK SH2 Cytokine receptor Y Y Y Y P P P Receptor tyrosinee kinase MAPK
Variations in mechanisms of STAT activation
SMAD family
SMAD-family - a logic resembling the STAT-family ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
TGF   effectors ,[object Object],[object Object]
Classification ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
SMAD-signalling pathway Effector SMADs (R-SMADs) C o-SMADs Repressor  SMADs
Three groups of SMADs ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
SMAD-signalling pathway
Final steps - target gene activation ,[object Object],[object Object],[object Object]
The Smad-factors activate their target genes in combination with other TFs
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Stat family :Role of Stat 3 in skin disorders by yousry