What does Smad mean?
Quantitative Proteomics of the SMAD (Suppressor of Mothers against Decapentaplegic) Transcription Factor Family Identifies Importin 5 as a Bone Morphogenic Protein Receptor SMAD-specific Importin* – Journal of Biological Chemistry.
Are Smad transcription factors?
Trimers of two receptor-regulated SMADs and one co-SMAD act as transcription factors that regulate the expression of certain genes.
What does the Smad pathway do?
The Smad-signaling pathway, which operates downstream of the transforming growth factor-β (TGF-β) superfamily of ligands, regulates a diverse set of biological processes, including proliferation, differentiation and apoptosis, in many different organ systems.
What is Smad phosphorylation?
Thus, phosphorylation of the Smad1 linker region provides the mechanism by which FGF and IGF attenuate BMP signaling, in order for neural differentiation to proceed. Also in Xenopus embryos, the TGF-β ligand activin can induce mesoderm markers in ectoderm, but the responsiveness is lost at particular embryonic stages.
How are Smad proteins activated?
Smad proteins belong to a family of proteins that are part of the TGF-β signaling pathway and negatively regulate the growth of epithelial cells. On binding of TGF-β, TGF-β receptor II activates TGF-β receptor I by phosphorylation. TGF-β receptor I in turn activates Smad2 and Smad3.
How many Smad proteins are there?
The seven mammalian Smad proteins are listed under their corresponding classes. In RSmads and Smad4, the MH1 domain contains a β-hairpin structure for binding to DNA. I-Smads lack MH1 domain. The linker region of RSmads contains multiple phosphorylation sites for MAPKs, CDKs, and other protein kinases.
Which Smad molecule is referred to as a co mediator?
They fall into three sub-classes, the receptor-regulated SMADs (R-SMADs), SMAD1, 2, 3, 5, and 9, the common mediator SMAD (co-SMAD) SMAD4, and the inhibitory SMADs (I-SMADs), SMAD6 and 7 (Figures 1 and 3; Table 1). The R-SMADs are highly conserved across all metazoans.
What is Smad dependent pathway?
Smad mediates the signal transduction in TGF-β and BMP signaling pathway that affects both osteoblast and osteoclast functions, and therefore plays a critical role in the regulation of bone remodeling.
Where is DPP expressed Drosophila?
anterior-posterior boundary
Dpp, a member of the BMP family, is a morphogen that specifies positional information in Drosophila wing precursors. In this tissue, Dpp expressed along the anterior-posterior boundary forms a concentration gradient that controls the expression domains of target genes, which in turn specify the position of wing veins.
How are SMAD and Smad-independent receptors activated and regulated?
Other signalling pathways further regulate Smad activation and function. In addition, TGF-beta receptors activate Smad-independent pathways that not only regulate Smad signalling, but also allow Smad-independent TGF-beta responses. Active Transport, Cell Nucleus
What is SMAD protein family?
The Smad protein family is an intracellular signaling protein identified in invertebrates by genetic screening methods in recent years ( Ma and Meng, 2019 ). The name of Smad gene is a combination of the Drosophila gene ‘mothers against decapentaplegic’ (Mad) and the Caenorhabditis elegans small protein (Sma) ( Derynck et al., 1996 ).
How do R-Smads and Smad4 interact with each other?
R-Smads and Smad4 interact with several DNA motifs though the MH1 domain. These motifs include the CAGAC and its CAGCC variant, as well as the 5-bp consensus sequence GGC (GC)| (CG). Receptor-phosphorylated R-Smads can form homotrimers, as well as heterotrimers with Smad4 in vitro, via interactions between the MH2 domains.
What is the PMID for SMAD?
PMID 15121845. ^ Kang Y, Chen CR, Massagué J (April 2003). “A self-enabling TGFbeta response coupled to stress signaling: Smad engages stress response factor ATF3 for Id1 repression in epithelial cells”.