CULLIN-RING ligases constitute the largest group of E3 ubiquitin ligases. While some CULLIN family members recruit adapters before engaging further with different substrate receptors, homo-dimeric BTB-Kelch family proteins combine adapter and substrate receptor into a single polypeptide for the CULLIN3 family. However, the entire structural assembly and molecular details have not been elucidated to date. Here, we present a cryo-EM structure of the CULLIN3 in complex with Kelch-like protein 22 (KLHL22) and a mitochondrial glutamate dehydrogenase complex I (GDH1) at 3.06 Å resolution. The structure adopts a W-shaped architecture formed by E3 ligase dimers. Three CULLIN3 dimers were found to be dynamically associated with a single GDH1 hexamer. CULLIN3 ligase mediated the polyubiquitination of GDH1 in vitro. Together, these results enabled the establishment of a structural model for understanding the complete assembly of BTB-Kelch proteins with CULLIN3 and how together they recognize oligomeric substrates and target them for ubiquitination.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.str.2023.09.002 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Cryo-EM analysis of complement C3 reveals a reversible major opening of the macroglobulin ring.
Nat Struct Mol Biol
January 2025
Department of Molecular Biology and Genetics, Aarhus, Denmark.
The C3 protein is the central molecule within the complement system and undergoes proteolytic activation to C3b in the presence of pathogens. Pattern-independent activation of C3 also occurs via hydrolysis, resulting in C3(HO), but the structural details of C3 hydrolysis remain elusive. Here we show that the conformation of the C3(HO) analog, C3MA, is indistinguishable from C3b.
View Article and Find Full Text PDFReceptor binding, structure, and tissue tropism of cattle-infecting H5N1 avian influenza virus hemagglutinin.
Cell
January 2025
Beijing Life Science Academy, Beijing 102200, China; CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, China; National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China. Electronic address:
The ongoing circulation of highly pathogenic avian influenza (HPAI) A (H5N1) viruses, particularly clade 2.3.4.
View Article and Find Full Text PDFProtocol for estimating the contrast transfer function and absolute tilt angle offset for cryo-electron tomography using CTFMeasure.
STAR Protoc
January 2025
Key Laboratory for Protein Sciences of Ministry of Education, School of Life Sciences, Tsinghua University, Beijing 100084, China; State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Beijing 100084, China; Beijing Frontier Research Center for Biological Structure, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China. Electronic address:
Contrast transfer function (CTF) estimation is essential to the data processing workflow of cryo-electron tomography (cryoET). Here, we present a protocol for CTF estimation of the cryoET tilt series with CTFMeasure. CTFMeasure can estimate the CTF parameters together with the absolute tilt angle offset of the sample.
View Article and Find Full Text PDFYeast Eukaryotic Initiation Factor 4B Remodels the MRNA Entry Site on the Small Ribosomal Subunit.
Biochemistry
January 2025
Department of Developmental Biology and Genetics, Indian Institute of Science, Bengaluru 560012, India.
Eukaryotic Initiation Factor 4 (eIF4) is a group of factors that activates mRNA for translation and recruit 43S preinitiation complex (PIC) to the mRNA 5' end, forming the 48S PIC. The eIF4 factors include mRNA 5' cap-binding protein eIF4E, ATP-dependent RNA helicase eIF4A, and scaffold protein eIF4G, which anchors eIF4A and eIF4E. Another eIF4 factor, eIF4B, stimulates the RNA helicase activity of eIF4A and facilitates mRNA recruitment.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!