Relate the general principles of signal transduction to the

Relate the general principles of signal transduction to the TLR4 pathway. Describe the TLR4 pathway, and indicate (if present):

   A. What initiates the signal?

   B. What adaptors and/or scaffolds are present? What molecules have kinase functions?

   C. What molecules have kinase functions?

   D. What G-proteins are involved?

   E. How are the genes turned on?

   F. What is the final product produced by the pathway?

Solution

A. As the TLR4 is a trans membrane protein and initiate intracellular NFKb pathway. it initiates by lipopolysaccride present in the bacterial cell membrane and can be activates by many viral pritein.

B. TLR4 the transmembrane protein uses two different sets of adaptors; Mal and MyD88, and TRAM and TRIF. These adaptor pairs couple two signalling pathways leading to the activation of nuclear factor B (NFB) and interferon response factor 3(IRF-3) respectively.

C. Mal has the kinase function. Bruton tyrosine kinase of Mal at Tyr86, strongly interacted TLR4 homodimer.

D. GRKs a family of seven mammalian serine and threonine protein kinases which are involved in the function of TLR4.