SMAD4
mammalian protein found in Homo sapiens
SMAD4, also called SMAD family member 4, Mothers against decapentaplegic homolog 4, or DPC4 (deleted in pancreatic cancer 4) is a highly conserved protein present in all metazoans. It belongs to the SMAD family of transcription factor proteins, which act as mediators of TGF-β signal transduction. The TGFβ family of cytokines regulates critical processes during the lifecycle of metazoans, with important roles during embryo development, tissue homeostasis, regeneration, and immune regulation.
SMAD 4 belongs to the co-SMAD group (common mediator SMAD), the second class of the SMAD family. SMAD4 is the only known co-SMAD in most metazoans. It also belongs to the Dwarfin family of proteins that modulate members of the TGFβ protein superfamily, a family of proteins that all play a role in the regulation of cellular responses. Mammalian SMAD4 is a homolog of the Drosophila protein "Mothers against decapentaplegic" named Medea.
SMAD4 interacts with R-Smads, such as SMAD2, SMAD3, SMAD1, SMAD5 and SMAD9 (also called SMAD8) to form heterotrimeric complexes. Transcriptional coregulators, such as WWTR1 (TAZ) interact with SMADs to promote their function. Once in the nucleus, the complex of SMAD4 and two R-SMADS binds to DNA and regulates the expression of different genes depending on the cellular context.
The public source identifies “SMAD4” as mammalian protein found in Homo sapiens. This brief keeps that definition visible, then builds a research path around SMAD4, mammalian and protein.
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This entry incorporates text from “SMAD4” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.