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1.
Aging Dis ; 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38502587

RESUMEN

UDP-GalNAc polypeptide N-acetylgalactosaminyltransferases (GalNAc-Ts) catalyze mucin-type O-glycosylation by transferring α-N-acetylgalactosamine (GalNAc) from UDP-GalNAc to Ser or Thr residues of target proteins. This post-translational modification is common in eukaryotes, yet its biological functions remain unclear. Recent studies have identified specific receptors in the heart and vascular wall cells that can be mucin-type O-glycosylated, and there is now substantial evidence confirming that patients with various cardiovascular diseases (CVDs), such as heart failure, coronary artery disease, myocardial hypertrophy, and vascular calcification, exhibit abnormal changes in GalNAc-Ts. This review aims to highlight recent advances in GalNAc-Ts and their roles in the cardiovascular system, intending to provide evidence for clinical treatment and prevention of CVDs.

2.
J Cell Biol ; 223(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429999

RESUMEN

Cholesterol from low-density lipoprotein (LDL) can be transported to many organelle membranes by non-vesicular mechanisms involving sterol transfer proteins (STPs). Fatty acid-binding protein (FABP) 7 was identified in our previous study searching for new regulators of intracellular cholesterol trafficking. Whether FABP7 is a bona fide STP remains unknown. Here, we found that FABP7 deficiency resulted in the accumulation of LDL-derived cholesterol in lysosomes and reduced cholesterol levels on the plasma membrane. A crystal structure of human FABP7 protein in complex with cholesterol was resolved at 2.7 Å resolution. In vitro, FABP7 efficiently transported the cholesterol analog dehydroergosterol between the liposomes. Further, the silencing of FABP3 and 8, which belong to the same family as FABP7, caused robust cholesterol accumulation in lysosomes. These two FABP proteins could transport dehydroergosterol in vitro as well. Collectively, our results suggest that FABP3, 7, and 8 are a new class of STPs mediating cholesterol egress from lysosomes.


Asunto(s)
Colesterol , Proteínas de Unión a Ácidos Grasos , Lisosomas , Humanos , Membrana Celular/metabolismo , Colesterol/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Lisosomas/metabolismo , Esteroles/metabolismo
3.
J Transl Med ; 22(1): 203, 2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38403590

RESUMEN

Resident memory T (Trm) cells which are specifically located in non-lymphoid tissues showed distinct phenotypes and functions compared to circulating memory T cells and were vital for the initiation of robust immune response within tissues. However, the heterogeneity in the transcriptional features, development pathways, and cancer response of Trm cells in the small intestine was not demonstrated. Here, we integrated scRNA-seq and scTCR-seq data pan-tissue T cells to explore the heterogeneity of Trm cells and their development pathways. Trm were enriched in tissue-specific immune response and those in the DUO specially interacted with B cells via TNF and MHC-I signatures. T cell lineage analyses demonstrated that Trm might be derived from the T_CD4/CD8 subset within the same organ or migrated from spleen and mesenteric lymph nodes. We compared the immune repertoire of Trm among organs and implied that clonotypes in both DUO and ILE were less expanded and hydrophilic TRB CDR3s were enriched in the DUO. We further demonstrated that Trm in the intestine infiltrated the colorectal cancer and several effector molecules were highly expressed. Finally, the TCGA dataset of colorectal cancer implied that the infiltration of Trm from the DUO and the ILE was beneficial for overall survival and the response to immune checkpoint blockade.


Asunto(s)
Neoplasias Colorrectales , Memoria Inmunológica , Humanos , Células T de Memoria , Relevancia Clínica , Linfocitos T CD8-positivos , Intestino Delgado , Análisis de la Célula Individual , Neoplasias Colorrectales/metabolismo
4.
Plant Biotechnol J ; 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38346083

RESUMEN

Plants grow rapidly for maximal production under optimal conditions; however, they adopt a slower growth strategy to maintain survival when facing environmental stresses. As salt stress restricts crop architecture and grain yield, identifying genetic variations associated with growth and yield responses to salinity is critical for breeding optimal crop varieties. OsDSK2a is a pivotal modulator of plant growth and salt tolerance via the modulation of gibberellic acid (GA) metabolism; however, its regulation remains unclear. Here, we showed that OsDSK2a can be phosphorylated at the second amino acid (S2) to maintain its stability. The gene-edited mutant osdsk2aS2G showed decreased plant height and enhanced salt tolerance. SnRK1A modulated OsDSK2a-S2 phosphorylation and played a substantial role in GA metabolism. Genetic analysis indicated that SnRK1A functions upstream of OsDSK2a and affects plant growth and salt tolerance. Moreover, SnRK1A activity was suppressed under salt stress, resulting in decreased phosphorylation and abundance of OsDSK2a. Thus, SnRK1A preserves the stability of OsDSK2a to maintain plant growth under normal conditions, and reduces the abundance of OsDSK2a to limit growth under salt stress. Haplotype analysis using 3 K-RG data identified a natural variation in OsDSK2a-S2. The allele of OsDSK2a-G downregulates plant height and improves salt-inhibited grain yield. Thus, our findings revealed a new mechanism for OsDSK2a stability and provided a valuable target for crop breeding to overcome yield limitations under salinity stress.

5.
Sci China Life Sci ; 66(12): 2701-2710, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37930474

RESUMEN

Male sterility is an important trait in rice for hybrid rice (Oryza sativa) breeding. However, the factors involved in dominant male sterility are largely unknown. Here, we identified a gene from Sanming dominant genic male sterile rice, named Sanming dominant male sterility (SMS), and reported that an epi-allele of this locus contributes to male sterility. Segregation analysis attributed dominant male sterility to a single locus, SMS, which we characterized using a male-sterile near isogenic line (NIL) of rice cultivar 93-11. The SMS locus was heterozygous in the male-sterile 93-11 NIL, containing an epi-allele identical to that in 93-11, and an epi-allele identical to that in rice cultivar Nipponbare, which we refer to as SMS9 and SMSN, respectively. SMS9 is silent and hyper-methylated, whereas SMSN is expressed and hypo-methylated in the 93-11 NIL. Overexpressing SMSN led to male sterility. Mutations in SMS rescued the male sterility of the 93-11 NIL. Interestingly, we observed the duplication of SMSN in Nipponbare, but did not observe the duplication of SMS9 in 93-11. Together, these findings suggest that the reduced methylation and enhanced expression of the SMSN epi-allele in the 93-11 NIL is responsible for its role in conferring dominant male sterility.


Asunto(s)
Oryza , Infertilidad Vegetal , Alelos , Oryza/genética , Fenotipo , Fitomejoramiento/métodos , Infertilidad Vegetal/genética
6.
Sci Total Environ ; 898: 165452, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37467989

RESUMEN

The continued deterioration of riparian ecosystems is a worldwide concern, which can lead to soil erosion, plant degradation, biodiversity loss, and water quality decline. Here, taking into account waste resource utilization and eco-environmental friendliness, the sediment-modified planting eco-concrete with both H. verticillata and T. orientalis (SEC-H&T) was prepared and explored for the first time to achieve sustainable riparian restoration. Concrete mechanical characterizations showed that the compressive strength and porosity of SEC with 30% sediment content could reach up to 15.8 MPa and 21.25%, respectively. The mechanical properties and the sediment utilization levels of SEC were appropriately balanced, and potentially toxic element leaching results verified the environmental safety of eco-concrete modified with dredged sediments. Plant physiological parameters of both aquatic plants (biomass, chlorophyll, protein and starch) were observed to reach the normal levels in SEC during the 30-day culture period, and T. orientalis seemed better adapted to SEC environment than H. verticillate. Importantly, compared to SEC-H and SEC-T, SEC-H&T could effectively reduce the concentrations of COD, TN and TP by 58.59%, 74.00% and 79.98% in water, respectively. Notably, water purification mechanisms by SEC-H&T were further elucidated from the perspective of microbial community responses. Shannon index of bacterial diversity and proliferation of specific populations dominating nutrient transformation (such as Bacillus and Nitrospira) was increased under the synergy of SEC and aquatic plants. Correspondingly, functional genes involved in nitrogen and phosphorus transformation (such as nosZ and phoU) were also enriched. Our study can not only showcase an effective and flexible approach to recycle dredged sediments into eco-concrete with low environment impacts, but also provide a promising alternative for sustainable riparian restoration.


Asunto(s)
Bacterias , Ecosistema , Biodiversidad , Biomasa , Calidad del Agua , Sedimentos Geológicos
7.
Cell Insight ; 2(1): 100076, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37192909

RESUMEN

Evidence shows that some class I human leucocyte antigen (HLA) alleles are related to durable HIV controls. The T18A TCR, which has the alloreactivity between HLA-B∗42:01 and HLA-B∗81:01 and the cross-reactivity with different antigen mutants, can sustain long-term HIV controls. Here the structural basis of the T18A TCR binding to the immunodominant HIV epitope TL9 (TPQDLNTML180-188) presented by HLA-B∗42:01 was determined and compared to T18A TCR binding to the TL9 presented by the allo-HLA-B∗81:01. For differences between HLA-B∗42:01 and HLA-B∗81:01, the CDR1α and CDR3α loops adopt a small rearrangement to accommodate them. For different conformations of the TL9 presented by different HLA alleles, not like the conventional recognition of CDR3s to interact with peptide antigens, CDR3ß of the T18A TCR shifts to avoid the peptide antigen but intensively recognizes the HLA only, which is different with other conventional TCR structures. Featured sequence pairs of CDR3ß and HLA might account for this and were additionally found in multiple other diseases indicating the popularity of the unconventional recognition pattern which would give insights into the control of diseases with epitope mutating such as HIV.

8.
Pharm Dev Technol ; 28(5): 452-459, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37104639

RESUMEN

This study aimed to improve the use of YF8, a matrine derivative obtained through chemical transformation of matrine extracted from Sophora alopecuroides. YF8 has demonstrated improved cytotoxicity compared to matrine, but its hydrophobic nature hinders its application. To overcome this, the lipid prodrug YF8-OA was synthesized by linking oleic acid (OA) to YF8 through an ester bond. Although YF8-OA could self-assemble into unique nanostructures in water, it was not sufficiently stable. To enhance the stability of YF8-OA lipid prodrug nanoparticles (LPs), we employed the strategy of PEGylation using DSPE-mPEG2000 or DSPE-mPEG2000 conjugated with folic acid (FA). This resulted in the formation of uniform spherical nanoparticles with greatly improved stability and a maximum drug load capacity upto 58.63%. Cytotoxicity was evaluated in A549, HeLa, and HepG2 cell lines. The results showed that in HeLa cells, the IC50 value of YF8-OA/LPs with FA-modified PEGylation was significantly lower than that of YF8-OA/LPs modified by PEGylation alone. However, no significant enhancement was observed in A549 and HepG2 cells. In conclusion, the lipid prodrug YF8-OA can form nanoparticles in aqueous solution to address its poor water solubility. Modification with FA resulted in further enhanced cytotoxicity, providing a potential avenue for exerting the antitumor activity of matrine analogs.


Asunto(s)
Antineoplásicos , Nanopartículas , Profármacos , Humanos , Profármacos/farmacología , Profármacos/química , Sistemas de Liberación de Medicamentos/métodos , Ácido Oléico , Células HeLa , Ácido Fólico/química , Lipopolisacáridos , Nanopartículas/química , Antineoplásicos/química
9.
IEEE Trans Pattern Anal Mach Intell ; 45(7): 7986-8002, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37015572

RESUMEN

Registration is a basic yet crucial task in point cloud processing. In correspondence-based point cloud registration, matching correspondences by point feature techniques may lead to an extremely high outlier (false correspondence) ratio. Current outlier removal methods still suffer from low efficiency, accuracy, and recall rate. We use an intuitive method to describe the 6-DOF (degree of freedom) curtailment process in point cloud registration and propose an outlier removal strategy based on the reliability of the correspondence graph. The method constructs the corresponding graph according to the given correspondences and designs the concept of the reliability degree of the graph node for optimal candidate selection and the reliability degree of the graph edge to obtain the global maximum consensus set. The presented method achieves fast and accurate outliers removal along with gradual aligning parameters estimation. Extensive experiments on simulations and challenging real-world datasets demonstrate that the proposed method can still perform effective point cloud registration even the correspondence outlier ratio is over 99%, and the efficiency is better than the state-of-the-art. Code is available at https://github.com/WPC-WHU/GROR.

11.
Structure ; 31(5): 511-517.e3, 2023 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-36990095

RESUMEN

F-box DNA helicase 1 (FBH1) is involved in the regulation of cell responses to replicative stress. FBH1 is recruited to stalled DNA replication fork by PCNA where it inhibits homologous recombination and catalyzes fork regression. Here, we report the structural basis for the molecular recognition of two distinctly different motifs of FBH1, FBH1PIP and FBH1APIM, by PCNA. The crystal structure of PCNA in complex with FBH1PIP and analysis of NMR perturbations reveal overlapped FBH1PIP and FBH1APIM binding sites of PCNA and the dominant contribution of FBH1PIP in this interaction.


Asunto(s)
ADN Helicasas , Replicación del ADN , ADN Helicasas/metabolismo , Recombinación Homóloga , Antígeno Nuclear de Célula en Proliferación/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo , Humanos
12.
Int Orthop ; 47(6): 1493-1510, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36897362

RESUMEN

PURPOSE: Total ankle replacement (TAR) or ankle arthrodesis (AA) is the main surgical treatment for end-stage ankle osteoarthritis. However, the therapeutic effect of the two surgical procedures at different follow-up times remains controversial. The purpose of this meta-analysis is to compare the short-term, medium-term, and long-term safety and efficiency of the two modern surgical treatments. METHODS: We conducted a comprehensive search in PubMed, EMBASE, Cochrane library databases, Web of Science, and Scopus. The main results were the patient's reported outcome measure (PROM) score, satisfaction, complications, reoperation, and surgery success rate. Different follow-up times and implant designs were used to evaluate the source of heterogeneity. We used a fixed effects model for meta-analysis and I2 statistic for evaluating heterogeneity. RESULTS: Thirty-seven comparative studies were included. In the short term, TAR significantly improved clinical scores (AOFAS score: WMD = 7.07, 95% Cl: 0.41-13.74, I2 = 0.0%; SF-36 PCS score: WMD = 2.40, 95% Cl: 2.22-2.58, I2 = 0.0%; SF-36 MCS score: WMD = 0.40, 95% Cl: 0.22-0.57, I2 = 0.0%; VAS for pain: WMD = - 0.50, 95% Cl: - 0.56-0.44, I2 = 44.3%) and had the lower incidence of revision (RR = 0.43, 95% CI: 0.23-0.81, I2 = 0.0%) and complications (RR = 0.67, 95% Cl: 0.50-0.90, I2 = 0.0%). In the medium term, there were still higher improvements in both the clinical scores (SF-36 PCS score: WMD = 1.57, 95% Cl: 1.36-1.78, I2 = 20.9%; SF-36 MCS score: WMD = 0.81, 95% Cl: 0.63-0.99, I2 = 48.8%) and the patient satisfaction (RR = 1.24, 95% Cl: 1.08-1.41, I2 = 12.1%) in the TAR group, but its total complications rate (RR = 1.84, 95% Cl: 1.26-2.68, I2 = 14.9%) and revision rate (RR = 1.58, 95% CI: 1.17-2.14, I2 = 84.6%) were significantly higher than that of the AA group. In the long term, there was no significant difference in clinical score and satisfaction, and a higher incidence of revision (RR = 2.32, 95% Cl: 1.70-3.16, I2 = 0.0%) and complications (RR = 3.18, 95% Cl: 1.69-5.99, I2 = 0.0%) was observed in TAR than in AA. The result of the third-generation design subgroup was consistent with that of the above pooled results. CONCLUSION: TAR had advantages over AA in the short term due to better performance in terms of PROMs, complications, and reoperation rates, but its complications become a disadvantage in the medium term. In the long term, AA seems to be favored because of lower complications and revision rates, although there is no difference in clinical scores.


Asunto(s)
Artroplastia de Reemplazo de Tobillo , Osteoartritis , Humanos , Artroplastia de Reemplazo de Tobillo/efectos adversos , Artroplastia de Reemplazo de Tobillo/métodos , Articulación del Tobillo/cirugía , Estudios de Seguimiento , Tobillo/cirugía , Resultado del Tratamiento , Osteoartritis/cirugía , Osteoartritis/complicaciones , Artrodesis/efectos adversos , Artrodesis/métodos , Estudios Retrospectivos
13.
Biomimetics (Basel) ; 7(4)2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36412705

RESUMEN

Effective integrated methods for oil-water separation and water remediation have signifi-cance in both energy and environment fields. Materials with both superlyophobic and superlyophilic properties toward water and oil have aroused great attention due to their energy-saving and high-efficient advantages in oil-water separation. However, in order to fulfill the superlyophobicity, low surface tension fluorinated components are always being introduced. These constituents are environmentally harmful, which may lead to additional contamination during the separating process. Moreover, the heavy metal ions, which are water-soluble and highly toxic, are always contained in the oil-water mixtures created during industrial production. Therefore, material that is integrated by both capacities of oil-water separation and removal of heavy metal contamination would be of significance in both industrial applications and environmental sustainability. Herein, inspired by the composition and wettability of the shrimp shell, an eco-friendly chitosan-coated (CTS) cotton was developed. The treated cotton exhibits the superhydrophilic/underwater superoleophobic property and is capable of separating both immiscible oil-water mixtures and stabilized oil-in-water emulsions. More significantly, various harmful water-soluble heavy metal ions can also be effectively removed during the separation of emulsions. The developed CTS coated cotton demonstrates an attractive perspective toward oil-water separation and wastewater treatment in various applications.

14.
Int J Mol Sci ; 23(19)2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36232627

RESUMEN

The SARS-CoV-2 Delta and Lambda variants had been named variants of concern (VOC) and variants of interest (VOI), respectively, by the World Health Organization (WHO). Both variants have two mutations in the spike receptor binding domain (RBD) region, with L452R and T478K mutations in the Delta variant, and L452Q and F490S mutations in the Lambda variant. We used surface plasmon resonance (SPR)-based technology to evaluate the effect of these mutations on human angiotensin-converting enzyme 2 (ACE2) and Bamlanivimab binding. The affinity for the RBD ligand, ACE2, of the Delta RBD is approximately twice as strong as that of the wild type RBD, an increase that accounts for the increased infectivity of the Delta variant. On the other hand, in spite of its amino acid changes, the Lambda RBD has similar affinity to ACE2 as the wild type RBD. The protective anti-wild type RBD antibody Bamlanivimab binds very poorly to the Delta RBD and not at all to the Lambda RBD. Nevertheless, serum antibodies from individuals immunized with the BNT162b2 vaccine were found to bind well to the Delta RBD, but less efficiently to the Lambda RBD in contrast. As a result, the blocking ability of ACE2 binding by serum antibodies was decreased more by the Lambda than the Delta RBD. Titers of sera from BNT162b2 mRNA vaccinated individuals dropped 3-fold within six months of vaccination regardless of whether the target RBD was wild type, Delta or Lambda. This may account partially for the fall off with time in the protective effect of vaccines against any variant.


Asunto(s)
COVID-19 , SARS-CoV-2 , Aminoácidos , Enzima Convertidora de Angiotensina 2/genética , Anticuerpos Monoclonales Humanizados , Anticuerpos Neutralizantes , Vacuna BNT162 , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Inmunidad Humoral , Ligandos , Mutación , ARN Mensajero , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , Vacunas Sintéticas , Vacunas de ARNm
15.
Genome Biol ; 23(1): 161, 2022 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-35879771

RESUMEN

Low efficiency has seriously restricted the application of prime editing (PE) systems in plants. In this study, we develop an enhanced plant prime editor 2 system, enpPE2, by stacking various optimization strategies, including updating the PE architecture to PEmax and expressing engineered pegRNA with a structured motif under the control of a composite promoter. In T0 rice plants, enpPE2 exhibits editing frequencies of 64.58% to 77.08%, which are much higher than the frequencies with unmodified pPE2. Our results indicate that the enpPE2 system provides a robust and powerful tool for the precise modification of plant genomes.


Asunto(s)
Edición Génica , Oryza , Sistemas CRISPR-Cas , Edición Génica/métodos , Genoma de Planta , Oryza/genética , Plantas/genética
16.
Biomolecules ; 12(3)2022 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-35327545

RESUMEN

The surreptitious discoveries of the protease activities on arginine-methylated targets of a subfamily of Jumonji domain-containing family including JMJD5, JMJD6, and JMJD7 pose several questions regarding their authenticity, function, purpose, and relations with others. At the same time, despite several decades of efforts and massive accumulating data regarding the roles of the arginine methyltransferase family (PRMTs), the exact function of this protein family still remains a mystery, though it seems to play critical roles in transcription regulation, including activation and inactivation of a large group of genes, as well as other biological activities. In this review, we aim to elucidate that the function of JMJD5/6/7 and PRMTs are likely coupled. Besides roles in the regulation of the biogenesis of membrane-less organelles in cells, they are major players in regulating stimulating transcription factors to control the activities of RNA Polymerase II in higher eukaryotes, especially in the animal kingdom. Furthermore, we propose that arginine methylation by PRMTs could be a ubiquitous action marked for destruction after missions by a subfamily of the Jumonji protein family.


Asunto(s)
Arginina , Proteína-Arginina N-Metiltransferasas , Animales , Arginina/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Metilación , Péptido Hidrolasas/metabolismo , Proteína-Arginina N-Metiltransferasas/genética
17.
Front Immunol ; 13: 825256, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35154144

RESUMEN

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has lasted more than 2 years with over 260 million infections and 5 million deaths worldwide as of November 2021. To combat the virus, monoclonal antibodies blocking the virus binding to human receptor, the angiotensin converting enzyme 2 (ACE2), have been approved to treat the infected patients. Inactivated whole virus or the full-length virus spike encoding adenovirus or mRNA vaccines are being used to immunize the public. However, SARS-CoV-2 variants are emerging. These, to some extent, escape neutralization by the therapeutic antibodies and vaccine-induced immunity. Thus, breakthrough infections by SARS-CoV-2 variants have been reported in previously virus-infected or fully vaccinated individuals. The receptor binding domain (RBD) of the virus spike protein reacts with host ACE2, leading to the entry of the virus into the cell. It is also the major antigenic site of the virus, with more than 90% of broadly neutralizing antibodies from either infected patients or vaccinated individuals targeting the spike RBD. Therefore, mutations in the RBD region are effective ways for SARS-CoV-2 variants to gain infectivity and escape the immunity built up by the original vaccines or infections. In this review, we focus on the impact of RBD mutations in SARS-CoV-2 variants of concern (VOC) and variants of interest (VOI) on ACE2 binding affinity and escape of serum antibody neutralization. We also provide protein structure models to show how the VOC and VOI RBD mutations affect ACE2 binding and allow escape of the virus from the therapeutic antibody, bamlanivimab.


Asunto(s)
SARS-CoV-2/genética , SARS-CoV-2/patogenicidad , Glicoproteína de la Espiga del Coronavirus/genética , Humanos , Mutación
18.
Cell Res ; 32(3): 288-301, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35121857

RESUMEN

Hedgehog (Hh) is a morphogen that binds to its receptor Patched 1 and activates Smoothened (SMO), thereby governing embryonic development and postnatal tissue homeostasis. Cholesterol can bind and covalently conjugate to the luminal cysteine-rich domain (CRD) of human SMO at the D95 residue (D99 in mouse). The reaction mechanism and biological function of SMO cholesterylation have not been elucidated. Here, we show that the SMO-CRD undergoes auto-cholesterylation which is boosted by calcium and involves an intramolecular ester intermediate. In cells, Hh stimulation elevates local calcium concentration in the SMO-localized endosomes through store-operated calcium entry. In addition, we identify the signaling-incompetent SMO D95E mutation, and the D95E mutant SMO can bind cholesterol but cannot be modified or activated by cholesterol. The homozygous SmoD99E/D99E knockin mice are embryonic lethal with severe developmental delay, demonstrating that cholesterylation of CRD is required for full-length SMO activation. Our work reveals the unique autocatalytic mechanism of SMO cholesterylation and an unprecedented role of calcium in Hh signaling.


Asunto(s)
Calcio , Proteínas Hedgehog , Animales , Colesterol , Ésteres , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Ratones , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal , Receptor Smoothened/genética , Receptor Smoothened/metabolismo
19.
Plant Biotechnol J ; 20(2): 350-359, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34582079

RESUMEN

Two type II-C Cas9 orthologs (Nm1Cas9 and Nm2Cas9) were recently identified from Neisseria meningitidis and have been extensively used in mammalian cells, but whether these NmCas9 orthologs or other type II-C Cas9 proteins can mediate genome editing in plants remains unclear. In this study, we developed and optimized targeted mutagenesis systems from NmCas9s for plants. Efficient genome editing at the target with N4 GATT and N4 CC protospacer adjacent motifs (PAMs) was achieved with Nm1Cas9 and Nm2Cas9 respectively. These results indicated that a highly active editing system could be developed from type II-C Cas9s with distinct PAM preferences, thus providing a reliable strategy to extend the scope of genome editing in plants. Base editors (BEs) were further developed from the NmCas9s. The editing efficiency of adenine BEs (ABEs) of TadA*-7.10 and cytosine BEs (CBEs) of rat APOBEC1 (rAPO1) or human APOBEC3a (hA3A) were extremely limited, whereas ABEs of TadA-8e and CBEs of Petromyzon marinus cytidine deaminase 1 (PmCDA1) exhibited markedly improved performance on the same targets. In addition, we found that fusion of a single-stranded DNA-binding domain from the human Rad51 protein enhanced the base editing capability of rAPO1-CBEs of NmCas9s. Together, our results suggest that the engineering of NmCas9s or other type II-C Cas9s can provide useful alternatives for crop genome editing.


Asunto(s)
Neisseria meningitidis , Oryza , Desaminasas APOBEC-1/genética , Adenina , Animales , Sistemas CRISPR-Cas/genética , Citidina Desaminasa , Edición Génica/métodos , Mamíferos/genética , Neisseria meningitidis/genética , Oryza/genética , Proteínas , Ratas
20.
Immunology ; 165(3): 341-354, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34967442

RESUMEN

Killer cell immunoglobulin-like receptors (KIRs) are important receptors for regulating the killing of virus-infected or cancer cells of natural killer (NK) cells. KIR2DS2 can recognize peptides derived from hepatitis C virus (HCV) or global flaviviruses (such as dengue and Zika) presented by HLA-C*0102 to activate NK cells, and has shown promising results when used for cancer immunotherapy. Here, we present the complex structure of KIR2DS2 with HLA-C*0102 at a resolution of 2·5Å. Our structure reveals that KIR2DS2 can bind with HLA-C*0102 and HLA-A*1101 in two different directions. Moreover, Tyr45 (in activating receptor KIR2DS2) and Phe45 (in inhibitory KIRs) distinguish the two different binding models and binding affinity between activating KIRs and inhibitory KIRs. The conserved 'AT' motif of the peptide mediates recognition and determines the peptide specificity of recognition. These structural characteristics shed light on how KIRs activate NK cells and can provide a molecular basis for immunotherapy by NK cells.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Antígenos HLA-C , Hepacivirus/metabolismo , Humanos , Células Asesinas Naturales , Péptidos/metabolismo , Receptores KIR/metabolismo
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