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1.
Science ; 383(6688): eadk4422, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484051

RESUMO

Conditional protein degradation tags (degrons) are usually >100 amino acids long or are triggered by small molecules with substantial off-target effects, thwarting their use as specific modulators of endogenous protein levels. We developed a phage-assisted continuous evolution platform for molecular glue complexes (MG-PACE) and evolved a 36-amino acid zinc finger (ZF) degron (SD40) that binds the ubiquitin ligase substrate receptor cereblon in complex with PT-179, an orthogonal thalidomide derivative. Endogenous proteins tagged in-frame with SD40 using prime editing are degraded by otherwise inert PT-179. Cryo-electron microscopy structures of SD40 in complex with ligand-bound cereblon revealed mechanistic insights into the molecular basis of SD40's activity and specificity. Our efforts establish a system for continuous evolution of molecular glue complexes and provide ZF tags that overcome shortcomings associated with existing degrons.


Assuntos
Degrons , Evolução Molecular Direcionada , Proteólise , Ubiquitina-Proteína Ligases , Dedos de Zinco , Microscopia Crioeletrônica , Talidomida/química , Ubiquitina-Proteína Ligases/química , Ubiquitinação , Degrons/genética , Dedos de Zinco/genética , Quimera de Direcionamento de Proteólise , Evolução Molecular Direcionada/métodos , Humanos
2.
Nat Chem ; 16(2): 218-228, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38110475

RESUMO

Proteolysis-targeting chimeras (PROTACs) are molecules that induce proximity between target proteins and E3 ligases triggering target protein degradation. Pomalidomide, a widely used E3 ligase recruiter in PROTACs, can independently degrade other proteins, including zinc-finger (ZF) proteins, with vital roles in health and disease. This off-target degradation hampers the therapeutic applicability of pomalidomide-based PROTACs, requiring development of PROTAC design rules that minimize off-target degradation. Here we developed a high-throughput platform that interrogates off-target degradation and found that reported pomalidomide-based PROTACs induce degradation of several ZF proteins. We generated a library of pomalidomide analogues to understand how functionalizing different positions of the phthalimide ring, hydrogen bonding, and steric and hydrophobic effects impact ZF protein degradation. Modifications of appropriate size on the C5 position reduced off-target ZF degradation, which we validated through target engagement and proteomics studies. By applying these design principles, we developed anaplastic lymphoma kinase oncoprotein-targeting PROTACs with enhanced potency and minimal off-target degradation.


Assuntos
Proteínas , Talidomida/análogos & derivados , Ubiquitina-Proteína Ligases , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Proteínas/metabolismo , Talidomida/farmacologia
3.
Cureus ; 15(1): e33945, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36820105

RESUMO

INTRODUCTION: Anthropometric measurements of the distal femoral fragment play a crucial role in prosthesis design during arthroplastic knee surgeries and offer valuable clues for stature estimation in forensic investigations. The present study is an attempt to assess various anthropometric parameters of the distal femur in this regard. MATERIALS AND METHODS: A total of 96 intact dry femora were anthropometrically assessed using digital Vernier calipers. The femoral length was measured using an osteometric table. The torsion angle was calculated with an analog goniometer. The various parameters studied included: medial condyle length and thickness, lateral condyle length and thickness, bicondylar width, intercondylar width, intercondylar depth, torsional angle, and femoral length. The data obtained were statistically analyzed using SPSS software (IBM Corp., Armonk, NY, USA). RESULTS: Mean medial condyle length was 57.38±4.47mm and thickness was 24.53±2.27mm. Mean lateral condyle length and thickness were found to be 58.49±4.3mm and 25.33±3.15mm respectively. Mean bicondylar width was 71.96±6.73mm, mean intercondylar width 21.86±2.71mm, and the intercondylar depth 27.04±2.59mm respectively. The average femur length was 41.87±3.31mm and the average torsion angle was 20.19°±6.99°. Significant correlations were observed between distal femoral parameters. Lateral condyle length showed maximum correlation with other parameters. Femur length was found to correlate significantly with all parameters except medial condyle thickness. Torsion angle was significantly correlated with lateral condyle length and femur length only. DISCUSSION: The findings of this study show considerable variation from those of other studies done within India. This proves that distal femoral anthropometry has regional variations. These data can aid sports physicians and orthopedic surgeons with implant designing and forensic experts during investigations.

4.
Front Microbiol ; 14: 1066096, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36876067

RESUMO

The present study deals with whole genome analysis of Fusarium udum, a wilt causing pathogen of pigeon pea. The de novo assembly identified a total of 16,179 protein-coding genes, of which 11,892 genes (73.50%) were annotated using BlastP and 8,928 genes (55.18%) from KOG annotation. In addition, 5,134 unique InterPro domains were detected in the annotated genes. Apart from this, we also analyzed genome sequence for key pathogenic genes involved in virulence, and identified 1,060 genes (6.55%) as virulence genes as per the PHI-BASE database. The secretome profiling of these virulence genes indicated the presence of 1,439 secretory proteins. Of those, an annotation of 506 predicted secretory proteins through CAZyme database indicated maximum abundance of Glycosyl hydrolase (GH, 45%) family proteins followed by auxiliary activity (AA) family proteins. Interestingly, the presence of effectors for cell wall degradation, pectin degradation, and host cell death was found. The genome comprised approximately 895,132 bp of repetitive elements, which includes 128 long terminal repeats (LTRs), and 4,921 simple sequence repeats (SSRs) of 80,875 bp length. The comparative mining of effector genes among different Fusarium species revealed five common and two specific effectors in F. udum that are related to host cell death. Furthermore, wet lab experiment validated the presence of effector genes like SIX (for Secreted in Xylem). We conclude that deciphering the whole genome of F. udum would be instrumental in understanding evolution, virulence determinants, host-pathogen interaction, possible control strategies, ecological behavior, and many other complexities of the pathogen.

5.
Cureus ; 14(9): e28780, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36225441

RESUMO

The anthropometry of the proximal femur holds great clinical significance in designing implants and prostheses for proximal femoral fractures and hip joint arthroplasties. Surgical fixation with a properly matched prosthesis plays a crucial role in improving long-term treatment outcomes and preventing post-operative complications such as osteolysis with aseptic loosening and increased load. The femur is also one of the most commonest used bones for stature estimation. Often during forensic investigations, only fragmented remains of femur are found available from which femoral length is estimated by application of linear regression equations. The estimated femoral length thus obtained is used for stature estimation of the unidentified individual. This study has measured nine bony parameters from the proximal femur in a total of 96 dry femora. These measurements include the vertical head diameter, neck diameter, neck thickness, neck length, neck shaft angle, the transverse diameter of the fovea, longitudinal diameter of the fovea, foveal depth, and the intertrochanteric line length. In addition, the total length of the femur was also measured. The results were tabulated and statistically analyzed using SPSS software, version 25. The mean femoral head diameter was observed to be 41.59±3.25 mm, mean foveal depth was found to be 2.95±0.75 mm, mean foveal transverse and longitudinal diameters were observed to be 11.38±2.35 mm and 15.94±3.37 mm, respectively. The mean neck diameter was 29.45±3.33 mm. Mean neck length and neck thickness were observed to be 36.06±4.94 mm and 27.61±2.71 mm, respectively. Neck shaft angle was noted to range from 109° to 128°, with a mean of 119.08°±5.18°. The mean length of the inter-trochanteric line was measured to be 41.92±3.9 mm. The mean femoral length was observed to be 42.11±2.91 cm. Significant positive correlations were found between the various measured proximal morphometric parameters of the femur. The length of the femur showed a maximum positive correlation with the vertical head diameter, followed by the neck diameter, thickness, and foveal depth. The findings of this study can throw further light on the existing data. They can serve as a guideline for designing better-matched prostheses and implants for hip surgeries in the eastern Uttar Pradesh population.

6.
Cureus ; 13(7): e16382, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34408936

RESUMO

Decomposition, or the process by which a corpse turns into a skeleton due to the destruction of the soft tissue, is very complicated. Humankind has used various methods to inhibit and delay decomposition changes over centuries. It includes mummification, embalming, and preservation of the body under low temperatures. In this report, we present a criminal case involving the conservation of the body using a paste made from clarified butter and turmeric powder, with the body simultaneously kept in an air-conditioned room. The body acquired a stiff, leathery appearance consistent with mummification. The subjacent layers of the muscles had a soft consistency and specified adipocere changes. Adipocere changes were present in most internal organs. This case report involves a certified hospital death with no disagreement over the after-death interval or the cause of death during the postmortem examination. The postmortem changes resulted from a unique method of body preservation: a combination of lower temperature (by air conditioner) and the application of clarified butter mixed with turmeric powder.

7.
Cureus ; 12(10): e10880, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33178532

RESUMO

Background In forensic proficiency, the distinct model applied for age estimation includes physical examination, i.e., evaluation of somatic maturity and post pubescence peculiarities, dental development, and radiological assessment of skeletal maturity usually of the hand and wrist. The Greulich and Pyle (GP) method of skeletal age (SA) determination is considered quicker and easier with a lower error percentage of prediction. The specificity and applicability of the GP atlas have been recapitulated in many studies. This study aims to assess the applicability and reproducibility of the GP atlas on a sample of the eastern Utter Pradesh (UP) population. Results Considering the whole study population, the SA of the male subjects was retarded by 0.89 years or 9.03 months, whereas the SA of females were retarded by 0.36 years or 4.33 months than the chronological age, respectively. Conclusion According to this study, it is concluded that the GP atlas may not be applicable for both males and females in the eastern Uttar Pradesh region. The factors responsible for delayed skeletal growth and maturation may vary depending on demographics, ethnicity, and genetics. Further, a detailed study will be conclusive on a greater population size assessing more accurate and precise insights on the applicability and reproducibility of GP atlas.

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