Publications by authors named "Lifeng Pan"

57 Publications

Discovery of a cooperative mode of inhibiting RIPK1 kinase.

Cell Discov 2021 Jun 1;7(1):41. Epub 2021 Jun 1.

Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China.

RIPK1, a death domain-containing kinase, has been recognized as an important therapeutic target for inhibiting apoptosis, necroptosis, and inflammation under pathological conditions. RIPK1 kinase inhibitors have been advanced into clinical studies for the treatment of various human diseases. One of the current bottlenecks in developing RIPK1 inhibitors is to discover new approaches to inhibit this kinase as only limited chemotypes have been developed. Here we describe Necrostatin-34 (Nec-34), a small molecule that inhibits RIPK1 kinase with a mechanism distinct from known RIPK1 inhibitors such as Nec-1s. Mechanistic studies suggest that Nec-34 stabilizes RIPK1 kinase in an inactive conformation by occupying a distinct binding pocket in the kinase domain. Furthermore, we show that Nec-34 series of compounds can synergize with Nec-1s to inhibit RIPK1 in vitro and in vivo. Thus, Nec-34 defines a new strategy to target RIPK1 kinase and provides a potential option of combinatorial therapy for RIPK1-mediated diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41421-021-00278-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8169668PMC
June 2021

Development of potent and selective inhibitors targeting the papain-like protease of SARS-CoV-2.

Cell Chem Biol 2021 Jun 27;28(6):855-865.e9. Epub 2021 Apr 27.

Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China. Electronic address:

The COVID-19 pandemic has been disastrous to society and effective drugs are urgently needed. The papain-like protease domain (PLpro) of SARS-CoV-2 (SCoV2) is indispensable for viral replication and represents a putative target for pharmacological intervention. In this work, we describe the development of a potent and selective SCoV2 PLpro inhibitor, 19. The inhibitor not only effectively blocks substrate cleavage and immunosuppressive function imparted by PLpro, but also markedly mitigates SCoV2 replication in human cells, with a submicromolar IC. We further present a convenient and sensitive activity probe, 7, and complementary assays to readily evaluate SCoV2 PLpro inhibitors in vitro or in cells. In addition, we disclose the co-crystal structure of SCoV2 PLpro in complex with a prototype inhibitor, which illuminates their detailed binding mode. Overall, these findings provide promising leads and important tools for drug discovery aiming to target SCoV2 PLpro.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chembiol.2021.04.020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8075810PMC
June 2021

LRRK2 G2019S kinase activity triggers neurotoxic NSF aggregation.

Brain 2021 Apr 20. Epub 2021 Apr 20.

CIBIO, Università degli Studi di Trento, Trento, Italy.

Parkinson's disease is characterized by the progressive degeneration of dopaminergic neurons within the substantia nigra pars compacta and the presence of protein aggregates in surviving neurons. The LRRK2 G2019S mutation is one of the major determinants of familial Parkinson's disease cases and leads to late-onset Parkinson's disease with pleomorphic pathology, including α-synuclein accumulation and deposition of protein inclusions. We demonstrated that LRRK2 phosphorylates N-ethylmaleimide sensitive factor (NSF). We observed aggregates containing NSF in basal ganglia specimens from patients with Parkinson's disease carrying the G2019S variant, and in cellular and animal models expressing the LRRK2 G2019S variant. We found that LRRK2 G2019S kinase activity induces the accumulation of NSF in toxic aggregates. Of note, the induction of autophagy cleared NSF aggregation and rescued motor and cognitive impairment observed in aged hG2019S bacterial artificial chromosome (BAC) mice. We suggest that LRRK2 G2019S pathological phosphorylation impacts on NSF biochemical properties, thus causing the formation of cytotoxic protein inclusions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/brain/awab073DOI Listing
April 2021

Phosphorylation regulates the binding of autophagy receptors to FIP200 Claw domain for selective autophagy initiation.

Nat Commun 2021 03 10;12(1):1570. Epub 2021 Mar 10.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.

The ULK complex initiates the autophagosome formation, and has recently been implicated in selective autophagy by interacting with autophagy receptors through its FIP200 subunit. However, the structural mechanism underlying the interactions of autophagy receptors with FIP200 and the relevant regulatory mechanism remain elusive. Here, we discover that the interactions of FIP200 Claw domain with autophagy receptors CCPG1 and Optineurin can be regulated by the phosphorylation in their respective FIP200-binding regions. We determine the crystal structures of FIP200 Claw in complex with the phosphorylated CCPG1 and Optineurin, and elucidate the detailed molecular mechanism governing the interactions of FIP200 Claw with CCPG1 and Optineurin as well as their potential regulations by kinase-mediated phosphorylation. In addition, we define the consensus FIP200 Claw-binding motif, and find other autophagy receptors that contain this motif within their conventional LC3-interacting regions. In all, our findings uncover a general and phosphoregulatable binding mode shared by many autophagy receptors to interact with FIP200 Claw for autophagosome biogenesis, and are valuable for further understanding the molecular mechanism of selective autophagy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-021-21874-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7946963PMC
March 2021

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition).

Autophagy 2021 Jan 8;17(1):1-382. Epub 2021 Feb 8.

University of Crete, School of Medicine, Laboratory of Clinical Microbiology and Microbial Pathogenesis, Voutes, Heraklion, Crete, Greece; Foundation for Research and Technology, Institute of Molecular Biology and Biotechnology (IMBB), Heraklion, Crete, Greece.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/15548627.2020.1797280DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7996087PMC
January 2021

Offloading Role of a Discrete Thioesterase in Type II Polyketide Biosynthesis.

mBio 2020 09 15;11(5). Epub 2020 Sep 15.

State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China

Type II polyketides are a group of secondary metabolites with various biological activities. In nature, biosynthesis of type II polyketides involves multiple enzymatic steps whereby key enzymes, including ketoacyl-synthase (KS), chain length factor (KS), and acyl carrier protein (ACP), are utilized to elongate the polyketide chain through a repetitive condensation reaction. During each condensation, the biosynthesis intermediates are covalently attached to KS or ACP via a thioester bond and are then cleaved to release an elongated polyketide chain for successive postmodification. Despite its critical role in type II polyketide biosynthesis, the enzyme and its corresponding mechanism for type II polyketide chain release through thioester bond breakage have yet to be determined. Here, kinamycin was used as a model compound to investigate the chain release step of type II polyketide biosynthesis. Using a genetic knockout strategy, we confirmed that AlpS is required for the complete biosynthesis of kinamycins. Further biochemical assays revealed high hydrolytic activity of AlpS toward a thioester bond in an aromatic polyketide-ACP analog, suggesting its distinct role in offloading the polyketide chain from ACP during the kinamycin biosynthesis. Finally, we successfully utilized AlpS to enhance the heterologous production of dehydrorabelomycin in by nearly 25-fold, which resulted in 0.50 g/liter dehydrorabelomycin in a simple batch-mode shake flask culture. Taken together, our results provide critical knowledge to gain an insightful understanding of the chain-releasing process during type II polyketide synthesis, which, in turn, lays a solid foundation for future new applications in type II polyketide bioproduction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/mBio.01334-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7492732PMC
September 2020

Decoding three distinct states of the Syntaxin17 SNARE motif in mediating autophagosome-lysosome fusion.

Proc Natl Acad Sci U S A 2020 09 19;117(35):21391-21402. Epub 2020 Aug 19.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, University of Chinese Academy of Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 200032 Shanghai, China;

Syntaxin17, a key autophagosomal -ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein, can associate with ATG8 family proteins SNAP29 and VAMP8 to facilitate the membrane fusion process between the double-membraned autophagosome and single-membraned lysosome in mammalian macroautophagy. However, the inherent properties of Syntaxin17 and the mechanistic basis underlying the interactions of Syntaxin17 with its binding proteins remain largely unknown. Here, using biochemical, NMR, and structural approaches, we systemically characterized Syntaxin17 as well as its interactions with ATG8 family proteins, SNAP29 and VAMP8. We discovered that Syntaxin17 alone adopts an autoinhibited conformation mediated by a direct interaction between its Habc domain and the Qa-SNARE motif. In addition, we revealed that the Qa-SNARE region of Syntaxin17 contains one LC3-interacting region (LIR) motif, which preferentially binds to GABARAP subfamily members. Importantly, the GABARAP binding of Syntaxin17 can release its autoinhibited state. The determined crystal structure of the Syntaxin17 LIR-GABARAP complex not only provides mechanistic insights into the interaction between Syntaxin17 and GABARAP but also reveals an unconventional LIR motif with a C-terminally extended 3 helix for selectively binding to ATG8 family proteins. Finally, we also elucidated structural arrangements of the autophagic Syntaxin17-SNAP29-VAMP8 SNARE core complex, and uncovered its conserved biochemical and structural characteristics common to all other SNAREs. In all, our findings reveal three distinct states of Syntaxin17, and provide mechanistic insights into the Syntaxin17-mediated autophagosome-lysosome fusion process.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.2006997117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7474698PMC
September 2020

Probing Protein-Protein Interactions with Label-Free Mass Spectrometry Quantification in Combination with Affinity Purification by Spin-Tip Affinity Columns.

Anal Chem 2020 03 12;92(5):3913-3922. Epub 2020 Feb 12.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.

We describe an affinity purification-mass spectrometry (AP-MS) method for probing the interactome of a special targeting protein. The AP was implemented with monolithic micro immobilized metal ion affinity chromatography columns (m-IMAC) which were prepared by photoinitiated polymerization in the tip of a pipet (spin-tip columns). The recombinant His-tagged protein (bait protein) was reversibly immobilized on the affinity column through the chelating group nitrilotriacetic acid (NTA)-Ni. The bait protein and its interacting partners can be easily eluted from the affinity matrix. The pulled-down cellular proteins were then analyzed with label-free quantitative proteomics. We used this method for probing the interactome concerning the GOLD (Golgi dynamics) domain of the autophagy-associated adaptor protein FYCO1. Totally, 96 proteins including seven literature-reported FYCO1-associating proteins were identified. Among them CCZ1 and MON1A were further biochemically validated, and the direct interaction between the FYCO1 GOLD domain with CCZ1 was confirmed by co-immunoprecipitation experiments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.analchem.9b05355DOI Listing
March 2020

Structural Basis of Autophagy Regulatory Proteins.

Adv Exp Med Biol 2019 ;1206:287-326

Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032, China.

Autophagy is an evolutionarily conserved lysosome-dependent intracellular degradation process that is essential for the maintenance of cellular homeostasis and adaptation to cellular stresses in eukaryotic cells. The most well-characterized type of autophagy, the macroautophagy, involves the progressive sequestration of cytoplasmic components into dedicated double-membraned vesicles called autophagosomes, which ultimately fuse with lysosomes to initiate the autophagic degradation of the sequestered cargo. In the past decade, our understanding of the molecular mechanism of macroautophagy has significantly evolved, with particular contributions from the biochemical and structural characterizations of autophagy-related proteins. In this chapter, we focus on some autophagy regulatory proteins involved in the macroautophagy pathway, summarize their currently known structures, and discuss their relevant molecular mechanisms from a perspective of structural biology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/978-981-15-0602-4_15DOI Listing
December 2019

Structure of Myosin VI/Tom1 complex reveals a cargo recognition mode of Myosin VI for tethering.

Nat Commun 2019 08 1;10(1):3459. Epub 2019 Aug 1.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200032, Shanghai, China.

Myosin VI plays crucial roles in diverse cellular processes. In autophagy, Myosin VI can facilitate the maturation of autophagosomes through interactions with Tom1 and the autophagy receptors, Optineurin, NDP52 and TAX1BP1. Here, we report the high-resolution crystal structure of the C-terminal cargo-binding domain (CBD) of Myosin VI in complex with Tom1, which elucidates the mechanistic basis underpinning the specific interaction between Myosin VI and Tom1, and uncovers that the C-terminal CBD of Myosin VI adopts a unique cargo recognition mode to interact with Tom1 for tethering. Furthermore, we show that Myosin VI can serve as a bridging adaptor to simultaneously interact with Tom1 and autophagy receptors through two distinct interfaces. In all, our findings provide mechanistic insights into the interactions of Myosin VI with Tom1 and relevant autophagy receptors, and are valuable for further understanding the functions of these proteins in autophagy and the cargo recognition modes of Myosin VI.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-019-11481-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6673701PMC
August 2019

Mechanistic insights into the interactions of NAP1 with the SKICH domains of NDP52 and TAX1BP1.

Proc Natl Acad Sci U S A 2018 12 20;115(50):E11651-E11660. Epub 2018 Nov 20.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200032 Shanghai, China

NDP52 and TAX1BP1, two SKIP carboxyl homology (SKICH) domain-containing autophagy receptors, play crucial roles in selective autophagy. The autophagic functions of NDP52 and TAX1BP1 are regulated by TANK-binding kinase 1 (TBK1), which may associate with them through the adaptor NAP1. However, the molecular mechanism governing the interactions of NAP1 with NDP52 and TAX1BP1, as well as the effects induced by TBK1-mediated phosphorylation of NDP52 and TAX1BP1, remains elusive. Here, we report the atomic structures of the SKICH regions of NDP52 and TAX1BP1 in complex with NAP1, which not only uncover the mechanistic bases underpinning the specific interactions of NAP1 with the SKICH domains of NDP52 and TAX1BP1 but also reveal the binding mode of a SKICH domain. Moreover, we uncovered that the SKICH domains of NDP52 and TAX1BP1 share a general binding mode to interact with NAP1. Finally, we also evaluated the currently known TBK1-mediated phosphorylation sites in the SKICH domains of NDP52 and TAX1BP1 on the basis of their interactions with NAP1. In all, our findings provide mechanistic insights into the interactions of NAP1 with NDP52 and TAX1BP1, and are valuable for further understanding the functions of these proteins in selective autophagy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.1811421115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6294882PMC
December 2018

Age, primary symptoms, and genotype characteristics of norovirus outbreaks in Shanghai schools in 2017.

Sci Rep 2018 10 15;8(1):15238. Epub 2018 Oct 15.

Center for Disease Control and Prevention of Pudong, 3039 Zhangyang Road, Pudong District, Shanghai, 200136, China.

Sixty norovirus outbreaks that occurred in Pudong District, Shanghai in 2017 and affected 959 people were summarised. Of the outbreaks, 29 (48.3%), 27 (45.0%), and 4 (6.7%) occurred in kindergartens, primary schools, and middle schools, respectively. Although the total number of outbreaks peaked in March (13/60, 21.7%), outbreaks in kindergartens and primary schools peaked in April (6/29, 20.7%) and March (8/27, 29.6%), respectively. Primary schools had the highest median number of cases per outbreak (19) and the highest proportion of cases (54.6%). The male-to-female case ratio differed among school classifications, with the highest male case ratio (69.2%) occurring in middle schools. Primary symptoms also differed across the school classifications. Molecular virology analysis showed that a single viral strain caused each outbreak at each school. In turn, 50.6, 28.8, and 20.6% of cases were infected by GII.4, GII.2, and GII.17, respectively. Vomiting was seen in 98.2, 97.3, and 88.6% of the subjects infected with noroviruses GII.17, GII.4, and GII.2, respectively, and nausea in 73.6, 43.9, and 39.0%. In conclusion, noroviruses mainly affect primary school and kindergarten students. GII.4, GII.2, and GII.17 are the main epidemic strains in the local area, and the primary symptoms differed by age and genotype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-018-33724-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6189194PMC
October 2018

TBK1 Suppresses RIPK1-Driven Apoptosis and Inflammation during Development and in Aging.

Cell 2018 09 23;174(6):1477-1491.e19. Epub 2018 Aug 23.

Department of Cell Biology, Harvard Medical School, 240 Longwood Ave., Boston, MA 02115, USA; Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 26 Qiuyue Rd., Pudong, 201210 Shanghai, China. Electronic address:

Aging is a major risk factor for both genetic and sporadic neurodegenerative disorders. However, it is unclear how aging interacts with genetic predispositions to promote neurodegeneration. Here, we investigate how partial loss of function of TBK1, a major genetic cause for amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) comorbidity, leads to age-dependent neurodegeneration. We show that TBK1 is an endogenous inhibitor of RIPK1 and the embryonic lethality of Tbk1 mice is dependent on RIPK1 kinase activity. In aging human brains, another endogenous RIPK1 inhibitor, TAK1, exhibits a marked decrease in expression. We show that in Tbk1 mice, the reduced myeloid TAK1 expression promotes all the key hallmarks of ALS/FTD, including neuroinflammation, TDP-43 aggregation, axonal degeneration, neuronal loss, and behavior deficits, which are blocked upon inhibition of RIPK1. Thus, aging facilitates RIPK1 activation by reducing TAK1 expression, which cooperates with genetic risk factors to promote the onset of ALS/FTD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cell.2018.07.041DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6128749PMC
September 2018

Structural bases of the assembly, recognition and disassembly of linear ubiquitin chain.

Biochim Biophys Acta Mol Cell Res 2018 Jul 5;1865(10):1410-1422. Epub 2018 Jul 5.

State Key Laboratory of Bioorganic and Natural Products Chemistry, University of Chinese Academy of Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, People's Republic of China; Collaborative Innovation Center of Chemistry for Life Sciences, University of Chinese Academy of Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, People's Republic of China. Electronic address:

Linear ubiquitin chain is a latest discovered type of poly-ubiquitin chain that is broadly involved in innate immune and inflammatory pathways. Dysfunctions in its assembly, recognition or disassembly are intimately related with numerous immunodeficiency or autoimmune diseases. Our understanding of the molecular mechanism for linear ubiquitin chain formation, recognition and disassembly has being significantly evolved in recent years, with particular contribution from the biochemical and structural characterizations of related proteins. Here, we focus on the relevant proteins for the synthesis, recognition and digestion of linear ubiquitin chain, and review recent findings to summarize currently known molecular mechanism from a perspective of structural biology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbamcr.2018.07.003DOI Listing
July 2018

Mechanistic Insights into Recognitions of Ubiquitin and Myosin VI by Autophagy Receptor TAX1BP1.

J Mol Biol 2018 09 27;430(18 Pt B):3283-3296. Epub 2018 Jun 27.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China; Collaborative Innovation Center of Chemistry for Life Sciences, University of Chinese Academy of Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China. Electronic address:

TAX1BP1, a ubiquitin-binding adaptor, plays critical roles in the innate immunity and selective autophagy. During autophagy, TAX1BP1 may not only function as an autophagy receptor to recruit ubiquitylated substrates for autophagic degradation, but also serve as a Myosin VI cargo adaptor protein for mediating the maturation of autophagosome. However, the mechanistic basis underlying the specific interactions of TAX1BP1 with ubiquitin and Myosin VI remains elusive. Here, using biochemical, NMR and structural analyses, we elucidate the detailed binding mechanism and uncover the key determinants for the interaction between TAX1BP1 and ubiquitin. In addition, we reveal that both tandem zinc-fingers of TAX1BP1 and the conformational rigidity between them are required for the Myosin VI binding of TAX1BP1, and ubiquitin and Myosin VI are mutually exclusive in binding to TAX1BP1. Collectively, our findings provide mechanistic insights into the dual functions of TAX1BP1 in selective autophagy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jmb.2018.06.030DOI Listing
September 2018

Structural Insights into a Flavin-Dependent [4 + 2] Cyclase that Catalyzes trans-Decalin Formation in Pyrroindomycin Biosynthesis.

Cell Chem Biol 2018 06 12;25(6):718-727.e3. Epub 2018 Apr 12.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China; State Key Laboratory of Microbial Metabolism, School of Life Science & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Huzhou Center of Bio-Synthetic Innovation, 1366 Hongfeng Road, Huzhou 313000, China. Electronic address:

Here, we provide structural insights into PyrE3, a flavin-dependent [4 + 2] cyclase that catalyzes trans-decalin formation in the biosynthesis of pyrroindomycins. PyrE3 shares an architecture/domain organization head-to-tail similarity with the members of the family of para-hydroxybenzoate hydroxylase (pHBH)-fold monooxygenases, and possesses a flavin adenine dinucleotide (FAD)-binding domain, a middle domain, and a C-terminal thioredoxin-like domain. The FAD-binding domain forms a central hub of the protein structure, and binds with FAD in a "closed" conformation of pHBH-fold family monooxygenases known for their highly dynamic catalytic processes. FAD plays an essential structural role in PyrE3, where it is amenable to redox change; however, redox change has little effect on [4 + 2] cyclization activity. PyrE3 appears to selectively accommodate a tetramate-containing, linear polyene intermediate in a highly positively charged pocket, which is located at the interface between the FAD-binding domain and the middle domain, and can accelerate trans-decalin formation likely through an endo-selective [4 + 2] transition state.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chembiol.2018.03.007DOI Listing
June 2018

The LRRK2 Variant E193K Prevents Mitochondrial Fission Upon MPP+ Treatment by Altering LRRK2 Binding to DRP1.

Front Mol Neurosci 2018 28;11:64. Epub 2018 Feb 28.

Dulbecco Telethon Institute, CIBIO, Università degli Studi di Trento, Trento, Italy.

Mutations in leucine-rich repeat kinase 2 gene () are associated with familial and sporadic Parkinson's disease (PD). LRRK2 is a complex protein that consists of multiple domains, including 13 putative armadillo-type repeats at the N-terminus. In this study, we analyzed the functional and molecular consequences of a novel variant, E193K, identified in an Italian family. E193K substitution does not influence LRRK2 kinase activity. Instead it affects LRRK2 biochemical properties, such as phosphorylation at Ser935 and affinity for 14-3-3ε. Primary fibroblasts obtained from an E193K carrier demonstrated increased cellular toxicity and abnormal mitochondrial fission upon 1-methyl-4-phenylpyridinium treatment. We found that E193K alters LRRK2 binding to DRP1, a crucial mediator of mitochondrial fission. Our data support a role for LRRK2 as a scaffolding protein influencing mitochondrial fission.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2018.00064DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5835904PMC
February 2018

Molecular epidemiology of genogroup II norovirus infections in acute gastroenteritis patients during 2014-2016 in Pudong New Area, Shanghai, China.

Gut Pathog 2018 23;10. Epub 2018 Feb 23.

1School of Public Health, Fudan University, Shanghai, 200032 China.

Background: Norovirus (NoV), a member of the Caliciviridae, is now recognized as the leading cause of acute gastroenteritis (AGE) worldwide. Globally, the GII.4 Sydney_2012 variant has predominated in NoV-related AGE since 2012, although the novel variant GII.17 has also been reported as responsible for gastroenteritis outbreaks in East Asia since 2014. This study aimed to disclose the recent genotype patterns of NoV genogroup II (GII) presenting in AGE patients in Pudong New Area of Shanghai through a laboratory-based syndromic surveillance system. The study further aimed to delineate the predominant strains circulating in the population.

Methods: Pudong New Area is located in eastern Shanghai and covers 20.89% of the Shanghai population. The laboratory-based syndromic surveillance system is composed of 12 sentinel hospitals among the 68 general hospitals in this area. AGE patients who sought medical care were sampled following an AGE surveillance protocol. Stool samples were collected from participating patients, and a standardized questionnaire was given to each patient by trained nurses to gain information on the disease profiles and demographics of the patients. Real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to screen the GI nd GII NoV and RT-PCR was used to amplify NoV GII partial capsid protein open reading frame 2 (ORF2). NoV Genotyping Tool (version 1.0, RIVM, MA Bilthoven, Netherlands) was used for genotyping, and a phylogenetic analysis was conducted by MEGA 7.0.

Results: During 2014-2016, among the 2069 virus-infected AGE cases, 65.88% were caused by NoV. NoV-AGE occurred most frequently in the periods from October to March. The patients with more severe diarrheal symptoms and vomiting were more likely to be infected by NoV. The main genotypes were GII.17 (44.69%) and GII.4 (39.26%), which dominated the NoV-AGE epidemics jointly or in turn, whereas a slight increase in GII.2 was observed beginning in May 2016. The GII.17 strains tended to cluster more with the Hu/JP/2014/GII.P17_GII.17/Kawasaki323 variants, representing novel prevalent strains. Among the GII.4 strains, the GII.4 Sydney_2012 variant was still the predominant strain.

Conclusions: NoV GII has become the main cause of virus-infected AGE in Pudong New Area, Shanghai. The predominant genotypes of NoV GII were GII.17 and GII.4. Comprehensive laboratory-based surveillance is important for clinical diagnosis and treatment. Identification of emerging new genotypes is also crucial for the prevention and control of NoV-infected AGE.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13099-018-0233-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5824483PMC
February 2018

Structural insights into the ubiquitin recognition by OPTN (optineurin) and its regulation by TBK1-mediated phosphorylation.

Autophagy 2018 2;14(1):66-79. Epub 2018 Feb 2.

a State Key Laboratory of Bioorganic and Natural Products Chemistry , Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , Shanghai , China.

OPTN (optineurin), a ubiquitin-binding scaffold protein, functions as an important macroautophagy/autophagy receptor in selective autophagy processes. Mutations in OPTN have been linked with human neurodegenerative diseases including ALS and glaucoma. However, the mechanistic basis underlying the recognition of ubiquitin by OPTN and its regulation by TBK1-mediated phosphorylation are still elusive. Here, we demonstrate that the UBAN domain of OPTN preferentially recognizes linear ubiquitin chain and forms an asymmetric 2:1 stoichiometry complex with the linear diubiquitin. In addition, our results provide new mechanistic insights into how phosphorylation of UBAN would regulate the ubiquitin-binding ability of OPTN and how disease-associated mutations in the OPTN UBAN domain disrupt its interaction with ubiquitin. Finally, we show that defects in ubiquitin-binding may affect the recruitment of OPTN to linear ubiquitin-decorated mutant Huntington protein aggregates. Taken together, our findings clarify the interaction mode between UBAN and linear ubiquitin chain in general, and expand our knowledge of the molecular mechanism of ubiquitin-decorated substrates recognition by OPTN as well as the pathogenesis of neurodegenerative diseases caused by OPTN mutations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/15548627.2017.1391970DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5846504PMC
February 2019

Structural Insights into SHARPIN-Mediated Activation of HOIP for the Linear Ubiquitin Chain Assembly.

Cell Rep 2017 Oct;21(1):27-36

State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, People's Republic of China. Electronic address:

The linear ubiquitin chain assembly complex (LUBAC) is the sole identified E3 ligase complex that catalyzes the formation of linear ubiquitin chain, and it is composed of HOIP, HOIL-1L, and SHARPIN. The E3 activity of HOIP can be effectively activated by HOIL-1L or SHARPIN, deficiency of which leads to severe immune system disorders. However, the underlying mechanism governing the HOIP-SHARPIN interaction and the SHARPIN-mediated activation of HOIP remains elusive. Here, we biochemically and structurally demonstrate that the UBL domain of SHARPIN specifically binds to the UBA domain of HOIP and thereby associates with and activates HOIP. We further uncover that SHARPIN and HOIL-1L can separately or synergistically bind to distinct sites of HOIP UBA with induced allosteric effects and thereby facilitate the E2 loading of HOIP for its activation. Thus, our findings provide mechanistic insights into the assembly and activation of LUBAC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.celrep.2017.09.031DOI Listing
October 2017

SPATA2 regulates the activation of RIPK1 by modulating linear ubiquitination.

Genes Dev 2017 06 12;31(11):1162-1176. Epub 2017 Jul 12.

Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201203, China.

Stimulation of cells with TNFα leads to the formation of the TNF-R1 signaling complex (TNF-RSC) to mediate downstream cellular fate decision. Activation of the TNF-RSC is modulated by different types of ubiquitination and may lead to cell death, including apoptosis and necroptosis, in both RIPK1-dependent and RIPK1-independent manners. Spata2 (spermatogenesis-associated 2) is an adaptor protein recruited into the TNF-RSC to modulate the interaction between the linear ubiquitin chain assembly complex (LUBAC) and the deubiquitinase CYLD (cylindromatosis). However, the mechanism by which Spata2 regulates the activation of RIPK1 is unclear. Here, we report that Spata2-deficient cells show resistance to RIPK1-dependent apoptosis and necroptosis and are also partially protected against RIPK1-independent apoptosis. Spata2 deficiency promotes M1 ubiquitination of RIPK1 to inhibit RIPK1 kinase activity. Furthermore, we provide biochemical evidence for the USP domain of CYLD and the PUB domain of the SPATA2 complex preferentially deubiquitinating the M1 ubiquitin chain in vitro. Spata2 deficiency also promotes the activation of MKK4 and JNK and cytokine production independently of RIPK1 kinase activity. Spata2 deficiency sensitizes mice to systemic inflammatory response syndrome (SIRS) induced by TNFα, which can be suppressed by RIPK1 inhibitor Nec-1s. Thus, Spata2 can regulate inflammatory response and cell death in both RIPK1-dependent and RIPK1-independent manners.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1101/gad.299776.117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5538438PMC
June 2017

USP25 regulates Wnt signaling by controlling the stability of tankyrases.

Genes Dev 2017 05 15;31(10):1024-1035. Epub 2017 Jun 15.

Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Pudong, Shanghai 201210, China.

Aberrant activation of the Wnt signaling pathway plays an important role in human cancer development. Wnt signaling is negatively regulated by Axin, a scaffolding protein that controls a rate-limiting step in the destruction of β-catenin, the central activator of the Wnt pathway. In Wnt-stimulated cells, Axin is rapidly modified by tankyrase-mediated poly(ADP-ribosyl)ation, which promotes the proteolysis of Axin and consequent stabilization of β-catenin. Thus, regulation of the levels and activity of tankyrases is mechanistically important in controlling Wnt signaling. Here, we identify ubiquitin-specific protease 25 (USP25) as a positive regulator of Wnt/β-catenin signaling. We found that USP25 directly interacted with tankyrases to promote their deubiquitination and stabilization. We demonstrated that USP25 deficiency could promote the degradation of tankyrases and consequent stabilization of Axin to antagonize Wnt signaling. We further characterized the interaction between TNKS1 and USP25 by X-ray crystal structure determination. Our results provide important new insights into the molecular mechanism that regulates the turnover of tankyrases and the possibility of targeting the stability of tankyrases by antagonizing their interaction with USP25 to modulate the Wnt/β-catenin pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1101/gad.300889.117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5495119PMC
May 2017

An outbreak of acute GII.17 norovirus gastroenteritis in a long-term care facility in China: The role of nursing assistants.

J Infect Public Health 2017 Nov - Dec;10(6):725-729. Epub 2017 Feb 9.

Shanghai Pudong New Area Center for Disease Control and Prevention, Fudan University Pudong Institute of Preventive Medicine, 3039 Zhangyang Road, Shanghai 200136, China. Electronic address:

More than 30 residents and nursing assistants in a geriatric nursing hospital developed acute gastroenteritis from December 7th to December 18th, 2014 in Shanghai, China. An immediate epidemiological investigation was conducted to identify the etiological agent of the outbreak, mode of transmission and the risk factors. Cases were investigated according to an epidemiological questionnaire. Samples from cases, highly transmissible environmental surfaces and drinking water were collected for pathogens detection. A retrospective cohort study was conducted to explore the transmission mode. A total of 34 cases were affected in this acute gastroenteritis outbreak, including 23 residents, 9 nursing assistants and 2 doctors. 13 out of 30 samples were positive for GII.17 norovirus, no other pathogen was detected. Nursing assistants who developed gastroenteritis symptoms had a higher attack rate in residents they cared than those who did not develop any gastroenteritis symptoms (p<0.001). The acute gastroenteritis outbreak was caused by GII.17 norovirus. Person-to-person close contact and contaminated environmental surfaces were the probable transmission route. Nursing assistants were considered to play an important role in the secondary spread of norovirus. The poor medical skill and personal hygiene habits of nursing assistants in China should be paid attention and improved urgently which is critically important to prevent hospital infections.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jiph.2016.10.007DOI Listing
June 2018

Hydroxyl regioisomerization of anthracycline catalyzed by a four-enzyme cascade.

Proc Natl Acad Sci U S A 2017 02 30;114(7):1554-1559. Epub 2017 Jan 30.

State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China;

Ranking among the most effective anticancer drugs, anthracyclines represent an important family of aromatic polyketides generated by type II polyketide synthases (PKSs). After formation of polyketide cores, the post-PKS tailoring modifications endow the scaffold with various structural diversities and biological activities. Here we demonstrate an unprecedented four-enzyme-participated hydroxyl regioisomerization process involved in the biosynthesis of kosinostatin. First, KstA15 and KstA16 function together to catalyze a cryptic hydroxylation of the 4-hydroxyl-anthraquinone core, yielding a 1,4-dihydroxyl product, which undergoes a chemically challenging asymmetric reduction-dearomatization subsequently acted by KstA11; then, KstA10 catalyzes a region-specific reduction concomitant with dehydration to afford the 1-hydroxyl anthraquinone. Remarkably, the shunt product identifications of both hydroxylation and reduction-dehydration reactions, the crystal structure of KstA11 with bound substrate and cofactor, and isotope incorporation experiments reveal mechanistic insights into the redox dearomatization and rearomatization steps. These findings provide a distinguished tailoring paradigm for type II PKS engineering.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.1610097114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5321016PMC
February 2017

Viral pathogens among elderly people with acute respiratory infections in Shanghai, China: Preliminary results from a laboratory-based surveillance, 2012-2015.

J Med Virol 2017 10 6;89(10):1700-1706. Epub 2017 Jul 6.

School of Public Health, Fudan University, Shanghai, China.

Acute respiratory infections (ARIs), with viral pathogens as the major contributors, are the most common illnesses worldwide, and increase the morbidity and mortality among the elderly population. The clinical and pathological features of elderly people with ARIs need to be identified for disease intervention. From January 1, 2012 through December 31, 2015, respiratory specimens from patients above 60 years old with ARIs were collected from the outpatient and inpatient settings of six sentinel hospitals in Pudong New Area. Each specimen was tested via multiplex polymerase chain reaction (PCR) for eight target viral etiologies including influenza, human rhinovirus (HRV), human para-influenza virus (PIV), adenovirus (ADV), respiratory syncytial virus (RSV), human metapneumovirus (hMPV), human coronavirus (hCoVs), and human bocavirus (hBoV). A total of 967 elderly patients with ARIs were enrolled, including 589 (60.91%) males, and the median age was 73 years old. 306 (31.64%) patients were tested positive for any one of the eight viruses, including 276 single infections and 30 co-infections. Influenza was the predominant virus (14.17%, 137/967), detected from 21.35% (76/356) of the outpatients and 9.98% (61/611) of the inpatients. Influenza infections presented two annual seasonal peaks during winter and summer. Compared with non-influenza patients, those with influenza were more likely to have fever, cough, sore throat, and fatigue. This study identified influenza as the leading viral pathogen among elderly with ARIs, and two seasonal epidemic peaks were observed in Shanghai. An influenza vaccination strategy needs to be advocated for the elderly population.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jmv.24751DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7166983PMC
October 2017

The novel norovirus genotype GII.17 is the predominant strain in diarrheal patients in Shanghai, China.

Gut Pathog 2016 26;8:49. Epub 2016 Oct 26.

Research Base of Key Laboratory of Surveillance and Early Warning on Infectious Disease in China CDC, Shanghai Pudong New Area Center for Disease Control and Prevention, 3039 Zhangyang Road, Shanghai, 200136 China.

In the winter of 2014-2015, a novel norovirus (NoV) strain (GII.17) was reported to be the major cause of gastroenteritis outbreaks in East Asia. To determine the time course of gastroenteritis infections associated with the GII.17 strain and whether GII.17 was the main epidemic strain in diarrheal patients in Shanghai, 2169 stool samples were collected and tested. The detection rate of NoV GI and GII NoV strains was 0.83 and 24.02%, respectively. Phylogenetic analysis confirmed that there were seven NoV genotypes, among which GII.4 and GII.17 were the main genotypes. The GII.17 strain was first detected in a sample collected on August 14th, 2014, and beginning in January 2015, the novel GII.17 strain replaced the GII.4 strain as the dominant NoV genotype causing acute gastroenteritis in patients in Shanghai.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13099-016-0131-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5081667PMC
October 2016

Structural insights into the interaction and disease mechanism of neurodegenerative disease-associated optineurin and TBK1 proteins.

Nat Commun 2016 09 13;7:12708. Epub 2016 Sep 13.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.

Optineurin is an important autophagy receptor involved in several selective autophagy processes, during which its function is regulated by TBK1. Mutations of optineurin and TBK1 are both associated with neurodegenerative diseases. However, the mechanistic basis underlying the specific interaction between optineurin and TBK1 is still elusive. Here we determine the crystal structures of optineurin/TBK1 complex and the related NAP1/TBK1 complex, uncovering the detailed molecular mechanism governing the optineurin and TBK1 interaction, and revealing a general binding mode between TBK1 and its associated adaptor proteins. In addition, we demonstrate that the glaucoma-associated optineurin E50K mutation not only enhances the interaction between optineurin and TBK1 but also alters the oligomeric state of optineurin, and the ALS-related TBK1 E696K mutation specifically disrupts the optineurin/TBK1 complex formation but has little effect on the NAP1/TBK1 complex. Thus, our study provides mechanistic insights into those currently known disease-causing optineurin and TBK1 mutations found in patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/ncomms12708DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5027247PMC
September 2016

Epidemiological characteristics and pathogens attributable to hand, foot, and mouth disease in Shanghai, 2008-2013.

J Infect Dev Ctries 2016 Jun 30;10(6):612-8. Epub 2016 Jun 30.

Pudong District Center for Disease Control and Prevention, Shanghai, China.

Introduction: Hand, foot, and mouth disease (HFMD) is a common childhood illness caused by enteroviruses. A passive surveillance system has been implemented in Shanghai Pudong since 2008 and etiology surveillance since 2009.We characterized the epidemiology and the etiology of HFMD in Pudong from 2008-2013.

Methodology: Health care providers were required to report any clinically diagnosed HFMD to Pudong District Center for Disease Control and Prevention. For all severe cases and randomly selected mild HFMD cases, throat or rectal swabs or feces were collected for enterovirus detection by real time reverse transcription polymerase chain reaction.

Results: A total of 50,149 cases were reported, with average 8,508 per year (range: 3,577-13,202) and average incidence of 167.5/100,000 persons (range: 81.4-254.1/100,000 persons). HFMD was more likely to occur in children under five years of age (85.6%), while severe cases were more likely to happen in children under three years of age (63.9%). Every year in May or June, HFMD peaked in the region; two peaks were observed from 2011 to 2013.The most common etiologic agents are EV71 and CA16.Different types of enterovirus circulate in different years. EV71 was the predominant pathogen in severe cases. The proportions of EV71 in severe cases was higher than in mild cases at the children's medical center (p<0.001).

Conclusions: HFMD remains an important public health issue in Shanghai. HFMD pathogen surveillance is required for more types of enteroviruses besides EV71 and CA16, which would give a better picture of the etiology of HFMD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3855/jidc.6118DOI Listing
June 2016

Structural basis of FYCO1 and MAP1LC3A interaction reveals a novel binding mode for Atg8-family proteins.

Autophagy 2016 08 31;12(8):1330-9. Epub 2016 May 31.

a State Key Laboratory of Biorganic and Natural Products Chemistry , Shanghai , China.

FYCO1 (FYVE and coiled-coil domain containing 1) functions as an autophagy adaptor in directly linking autophagosomes with the microtubule-based kinesin motor, and plays an essential role in the microtubule plus end-directed transport of autophagic vesicles. The specific association of FYCO1 with autophagosomes is mediated by its interaction with Atg8-family proteins decorated on the outer surface of autophagosome. However, the mechanistic basis governing the interaction between FYCO1 and Atg8-family proteins is largely unknown. Here, using biochemical and structural analyses, we demonstrated that FYCO1 contains a unique LC3-interacting region (LIR), which discriminately binds to mammalian Atg8 orthologs and preferentially binds to the MAP1LC3A and MAP1LC3B. In addition to uncovering the detailed molecular mechanism underlying the FYCO1 LIR and MAP1LC3A interaction, the determined FYCO1-LIR-MAP1LC3A complex structure also reveals a unique LIR binding mode for Atg8-family proteins, and demonstrates, first, the functional relevance of adjacent sequences C-terminal to the LIR core motif for binding to Atg8-family proteins. Taken together, our findings not only provide new mechanistic insight into FYCO1-mediated transport of autophagosomes, but also expand our understanding of the interaction modes between LIR motifs and Atg8-family proteins in general.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/15548627.2016.1185590DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4968224PMC
August 2016