This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1mhd
From Proteopedia
CRYSTAL STRUCTURE OF A SMAD MH1 DOMAIN BOUND TO DNA
Structural highlights
Disease[SMAD3_HUMAN] Defects in SMAD3 may be a cause of colorectal cancer (CRC) [MIM:114500]. Defects in SMAD3 are the cause of Loeys-Dietz syndrome 3 (LDS3) [MIM:613795]. An aortic aneurysm syndrome with widespread systemic involvement. The disorder is characterized by the triad of arterial tortuosity and aneurysms, hypertelorism, and bifid uvula or cleft palate. Patients with LDS3 also manifest early-onset osteoarthritis. They lack craniosynostosis and mental retardation. Note=SMAD3 mutations have been reported to be also associated with thoracic aortic aneurysms and dissection (TAAD) (PubMed:21778426). This phenotype is distinguised from LDS3 by having aneurysms restricted to thoracic aorta. As individuals carrying these mutations also exhibit aneurysms of other arteries, including abdominal aorta, iliac, and/or intracranial arteries (PubMed:21778426), they have been classified as LDS3 by the OMIM resource.[1] [2] Function[SMAD3_HUMAN] Receptor-regulated SMAD (R-SMAD) that is an intracellular signal transducer and transcriptional modulator activated by TGF-beta (transforming growth factor) and activin type 1 receptor kinases. Binds the TRE element in the promoter region of many genes that are regulated by TGF-beta and, on formation of the SMAD3/SMAD4 complex, activates transcription. Also can form a SMAD3/SMAD4/JUN/FOS complex at the AP-1/SMAD site to regulate TGF-beta-mediated transcription. Has an inhibitory effect on wound healing probably by modulating both growth and migration of primary keratinocytes and by altering the TGF-mediated chemotaxis of monocytes. This effect on wound healing appears to be hormone-sensitive. Regulator of chondrogenesis and osteogenesis and inhibits early healing of bone fractures (By similarity). Positively regulates PDPK1 kinase activity by stimulating its dissociation from the 14-3-3 protein YWHAQ which acts as a negative regulator.[3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe Smad family of proteins, which are frequently targeted by tumorigenic mutations in cancer, mediate TGF-beta signaling from cell membrane to nucleus. The crystal structure of a Smad3 MH1 domain bound to an optimal DNA sequence determined at 2.8 A resolution reveals a novel DNA-binding motif. In the crystals, base-specific DNA recognition is provided exclusively by a conserved 11-residue beta hairpin that is embedded in the major groove of DNA. A surface loop region, to which tumorigenic mutations map, has been identified as a functional surface important for Smad activity. This structure establishes a framework for understanding how Smad proteins may act in concert with other transcription factors in the regulation of TGF-beta-responsive genes. Crystal structure of a Smad MH1 domain bound to DNA: insights on DNA binding in TGF-beta signaling.,Shi Y, Wang YF, Jayaraman L, Yang H, Massague J, Pavletich NP Cell. 1998 Sep 4;94(5):585-94. PMID:9741623[14] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||
Categories: Human | Shi, Y | Dna | Smad binding element | Smad3 mh1
