FYN binding protein (FYB-120/130), also known as FYB, ADAP (Adhesion and degranulation-promoting adapter protein), and SLAP-130 (SLP-76-associated phosphoprotein) is a protein that is encoded by the FYBgene in humans.[5] The protein is expressed in T cells, monocytes, mast cells, macrophages, NK cells, but not B cells.[6][7][8][9] FYB is a multifunctional protein involved in post-activation T cell signaling, lymphocyte cytokine production, cell adhesion, and actin remodeling.[7][8][9][10][11]
Two isoforms of FYB with different lengths of 120 and 130 kDa (FYB-120 and FYB-130) exist.[8] The 130kDa version has an extra insertion of 46 amino acids and is preferentially expressed in peripheral T cells.[8] The FYB protein has a variety of binding domains: a non-structured N-terminal region, a proline-rich region, two SH3 domains, a FPPP-motif which binds the ENA/VASP protein family, and other tyrosine-based signaling motifs.[11]
FYB regulates cytokine production in T cells as well as in activated NK cells through the FYN-ADAP axis.[9] In T cells, after TCR stimulation, a unique region of FYB, pYDGI, allows phosphorylation of the protein by FYN.[9] After being phosphorylated, ADAP can bind to Carma1, causing NF-κB translocation into the nucleus and cytokine production.[9]
In mast cells, FYB regulates cell adhesion as well as degranulation.[7] In T cells, FYB allows for cell adhesion and migration through blood vessels through the SLP-76-FYB-SKAP1 complex.[10] After being phosphorylated by FYN, FYB can bind to SLP-76.[7] This binding of FYB and SLP-76 regulates "outside-in signaling" or the transfer of signals from outside the cell to inside the cell by integrin.[10] FYB can also bind to SKAP1, which allows SKAP1 to upregulate integrin activity through interactions with Rap1.[8][10] The bacteria Yersinia can interfere with this pathway in macrophages through the secretion of YopH (Yersinia protein tyrosine phosphatase) into the macrophage, which de-phosphorylates FYB and SKAP1, leading to a decrease in integrin activity that results in an inhibition of adhesion, phagocytosis, and cytotoxicity.[8]
FYB is also an important protein for actin remodeling of immune cells.[11] This is thought to occur through the binding of proteins of the ENA/VASP protein family to the FPPPP-motif of the FYB protein.[11]
^Schraven B, Marie-Cardine A, Koretzky G (June 1997). "Molecular analysis of the fyn-complex: cloning of SKAP55 and SLAP-130, two novel adaptor proteins which associate with fyn and may participate in the regulation of T cell receptor-mediated signaling". Immunology Letters. 57 (1–3): 165–169. doi:10.1016/s0165-2478(97)00053-9. PMID9232446.
^ abcdGriffiths EK, Penninger JM (June 2002). "Communication between the TCR and integrins: role of the molecular adapter ADAP/Fyb/Slap". Current Opinion in Immunology. 14 (3): 317–322. doi:10.1016/s0952-7915(02)00334-5. PMID11973129.
Hamid N, Gustavsson A, Andersson K, McGee K, Persson C, Rudd CE, Fällman M (October 1999). "YopH dephosphorylates Cas and Fyn-binding protein in macrophages". Microbial Pathogenesis. 27 (4): 231–242. doi:10.1006/mpat.1999.0301. PMID10502464.
Brill LM, Salomon AR, Ficarro SB, Mukherji M, Stettler-Gill M, Peters EC (May 2004). "Robust phosphoproteomic profiling of tyrosine phosphorylation sites from human T cells using immobilized metal affinity chromatography and tandem mass spectrometry". Analytical Chemistry. 76 (10): 2763–2772. doi:10.1021/ac035352d. PMID15144186.
Heuer K, Arbuzova A, Strauss H, Kofler M, Freund C (May 2005). "The helically extended SH3 domain of the T cell adaptor protein ADAP is a novel lipid interaction domain". Journal of Molecular Biology. 348 (4): 1025–1035. doi:10.1016/j.jmb.2005.02.069. PMID15843031.
1ri9: Structure of a helically extended SH3 domain of the T cell adapter protein ADAP
2gtj: Reduced form of ADAP hSH3-N-domain
2gto: Oxidized form of ADAP hSH3-N
One thought on “Cannabaceae”
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction