Conventional approaches to identify secreted factors that regulate homeostasis are limited in their abilities to identify the tissues/cells of origin and destination. We established a platform to ...identify secreted protein trafficking between organs using an engineered biotin ligase (BirA*G3) that biotinylates, promiscuously, proteins in a subcellular compartment of one tissue. Subsequently, biotinylated proteins are affinity-enriched and identified from distal organs using quantitative mass spectrometry. Applying this approach in Drosophila, we identify 51 muscle-secreted proteins from heads and 269 fat body-secreted proteins from legs/muscles, including CG2145 (human ortholog ENDOU) that binds directly to muscles and promotes activity. In addition, in mice, we identify 291 serum proteins secreted from conditional BirA*G3 embryo stem cell-derived teratomas, including low-abundance proteins with hormonal properties. Our findings indicate that the communication network of secreted proteins is vast. This approach has broad potential across different model systems to identify cell-specific secretomes and mediators of interorgan communication in health or disease.
We report resonant-cavity infrared detectors with 34% external quantum efficiency at room temperature at the resonant wavelength of 4.0 μm, even though the absorber consists of only five quantum ...wells with a total thickness of 50 nm. The full width at half maximum (FWHM) linewidth is 46 nm, and the peak absorption is enhanced by nearly a factor of 30 over that for a single pass through the absorber. In spite of an unfavorable Shockley-Read lifetime in the current material, the dark current density is at the level of state-of-the-art HgCdTe detectors as quantified by "Rule 07." The Johnson-noise limited detectivity (D*) at 21°C is 7 × 10
cm Hz
/W. We expect that future improvements in the device design and material quality will lead to higher quantum efficiency, as well as a significant reduction of the dark current density consistent with the very thin absorber.
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P2X4 receptor has become an interesting molecular target for treatment and PET imaging of neuroinflammation and associated brain diseases such as Alzheimer’s disease. This study ...reports the first design, synthesis, radiolabeling and biological evaluation of new candidate PET P2X4 receptor radioligands using 5-BDBD, a specific P2X4 receptor antagonist, as a scaffold. 5-(3-Hydroxyphenyl)-1-11Cmethyl-1,3-dihydro-2H-benzofuro3,2-e1,4diazepin-2-one (N-11CMe-5-BDBD analog, 11C9) and 5-(3-Bromophenyl)-1-11Cmethyl-1,3-dihydro-2H-benzofuro3,2-e1,4diazepin-2-one (N-11CMe-5-BDBD, 11C8c) were prepared from their corresponding desmethylated precursors with 11CCH3OTf through N-11Cmethylation and isolated by HPLC combined with SPE in 30–50% decay corrected radiochemical yields with 370–1110GBq/µmol specific activity at EOB. 5-(3-18FFluorophenyl)-1,3-dihydro-2H-benzofuro3,2-e1,4diazepin-2-one (18FF-5-BDBD, 18F5a) and 5-(3-(2-18Ffluoroethoxy)phenyl)-1,3-dihydro-2H-benzofuro3,2-e1,4diazepin-2-one (18FFE-5-BDBD, 18F11) were prepared from their corresponding nitro- and tosylated precursors by nucleophilic substitution with K18FF/Kryptofix 2.2.2 and isolated by HPLC-SPE in 5–25% decay corrected radiochemical yields with 111–740GBq/µmol specific activity at EOB. The preliminary biological evaluation of radiolabeled 5-BDBD analogs indicated these new radioligands have similar biological activity with their parent compound 5-BDBD.
We report a resonant cavity infrared detector (RCID) with an InAsSb/InAs superlattice absorber with a thickness of only ≈ 100 nm, a 33-period GaAs/Al 0.92 Ga 0.08 As distributed Bragg reflector ...bottom mirror, and a Ge/SiO 2 /Ge top mirror. At a low bias voltage of 150 mV, the external quantum efficiency (EQE) reaches 58% at the resonance wavelength λ res ≈ 4.6 µm, with linewidth δλ = 19-27 nm. The thermal background current for a realistic system scenario with f/4 optic that views a 300 K scene is estimated by integrating the photocurrent generated by background spanning the entire mid-IR spectral band (3-5 µm). The resulting specific detectivity is a factor of 3 lower than for a state-of-the-art broadband HgCdTe device at 300 K, where dark current dominates the noise. However, at 125 K where the suppression of background noise becomes critical, the estimated specific detectivity D * of 5.5 × 10 12 cm Hz ½ /W is more than 3× higher. This occurs despite a non-optimal absorber cut-off that causes the EQE to decrease rapidly with decreasing temperature, e.g., to 33% at 125 K. The present RCID’s advantage over the broadband device depends critically on its low EQE at non-resonance wavelengths: ≤ 1% in the range 3.9-5.5 µm. Simulations using NRL MULTIBANDS indicate that impact ionization in the bottom contact and absorber layers dominates the dark current at near ambient temperatures. We expect future design modifications to substantially enhance D * throughout the investigated temperature range of 100-300 K.
Membrane trafficking is a complex, essential process in eukaryotic cells responsible for protein transport and processing. Deficiencies in vacuolar protein sorting (VPS) proteins, key regulators of ...trafficking, cause abnormal intracellular segregation of macromolecules and organelles and are linked to human disease. VPS proteins function as part of complexes such as the homotypic fusion and vacuole protein sorting (HOPS) tethering complex, composed of VPS11, VPS16, VPS18, VPS33A, VPS39 and VPS41. The HOPS-specific subunit VPS41 has been reported to promote viability of dopaminergic neurons in Parkinson's disease but to date has not been linked to human disease. Here, we describe five unrelated families with nine affected individuals, all carrying homozygous variants in VPS41 that we show impact protein function. All affected individuals presented with a progressive neurodevelopmental disorder consisting of cognitive impairment, cerebellar atrophy/hypoplasia, motor dysfunction with ataxia and dystonia, and nystagmus. Zebrafish disease modelling supports the involvement of VPS41 dysfunction in the disorder, indicating lysosomal dysregulation throughout the brain and providing support for cerebellar and microglial abnormalities when vps41 was mutated. This provides the first example of human disease linked to the HOPS-specific subunit VPS41 and suggests the importance of HOPS complex activity for cerebellar function.
Schizophrenia is a severely debilitating psychiatric disease that is hypothesized to have its roots in neurodevelopment. Although the precise neuropathology underlying schizophrenia has remained ...elusive, there are consistent reports of abnormalities in several brain areas. Chief among these is the hippocampus, an area which has displayed both structural and functional abnormalities in many schizophrenic patients. In order to better understand how disruption of hippocampal development may contribute to the etiology of psychiatric disease, we investigated the function of a highly promising schizophrenia susceptibility gene, DISC1 (Disrupted-In-Schizophrenia 1), in the development of the hippocampus. DISC1 is strongly expressed in the hippocampus from its early development through adulthood and has been implicated in hippocampal structure and function in human studies. However, its precise role in the development of the hippocampus is not yet known. Here, we show that in utero electroporation of Disc1 shRNA into the developing mouse hippocampus hinders the migration of dentate gyrus granule cells. Intriguingly, Disc1 knockdown does not affect the migration of CA1 pyramidal neurons, suggesting that Disc1's role in regulating neuronal migration is spatially restricted within the hippocampus. These findings support the idea that DISC1 abnormalities that contribute to the onset of schizophrenia may do so through their influences on hippocampal development.
Organ functions are highly specialized and interdependent. Secreted factors regulate organ development and mediate homeostasis through serum trafficking and inter-organ communication. ...Enzyme-catalysed proximity labelling enables the identification of proteins within a specific cellular compartment. Here, we report a
mouse strain that enables CRE-dependent promiscuous biotinylation of proteins trafficking through the endoplasmic reticulum. When broadly activated throughout the mouse, widespread labelling of proteins was observed within the secretory pathway. Streptavidin affinity purification and peptide mapping by quantitative mass spectrometry (MS) proteomics revealed organ-specific secretory profiles and serum trafficking. As expected, secretory proteomes were highly enriched for signal peptide-containing proteins, highlighting both conventional and non-conventional secretory processes, and ectodomain shedding. Lower-abundance proteins with hormone-like properties were recovered and validated using orthogonal approaches. Hepatocyte-specific activation of BirA*G3 highlighted liver-specific biotinylated secretome profiles. The BirA*G3 mouse model demonstrates enhanced labelling efficiency and tissue specificity over viral transduction approaches and will facilitate a deeper understanding of secretory protein interplay in development, and in healthy and diseased adult states.
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The reference standards halo-GSK1482160 (F-, Br-, and I-) and their corresponding precursors desmethyl-halo-GSK1482160 (F-, Br-, and I-) were synthesized from ...(S)-1-methyl-5-oxopyrrolidine-2-carboxylic acid or (S)-5-oxopyrrolidine-2-carboxylic acid and 2-halo-3-(trifluoromethyl)benzylamine (F-, Br-, and I-) in one step with 45–93% yields. The target tracers 11Chalo-GSK1482160 (F-, Br-, and I-) were prepared from desmethyl-halo-GSK1482160 (F-, Br-, and I-) with 11CCH3OTf under basic conditions (NaOH-Na2CO3, solid, w/w 1:2) through N-11Cmethylation and isolated by HPLC combined with SPE in 40–50% decay corrected radiochemical yield. The radiochemical purity was >99%, and the molar activity (AM) at end of bombardment (EOB) was 370–740 GBq/μmol. The potency of halo-GSK1482160 (F-, Br-, and I-) in comparison with GSK1482160 (Cl-) was determined by a radioligand competitive binding assay using 11CGSK1482160, and the binding affinity Ki values for halo-GSK1482160 (F-, Br-, and I-) and GSK1482160 (Cl-) are 54.2, 2.5, 1.9 and 3.1 nM, respectively.
An immunogenetic view of COVID-19 Aguiar, Vitor R C; Augusto, Danillo G; Castelli, Erick C ...
Genetics and Molecular Biology,
01/2021, Letnik:
44, Številka:
1 Suppl 1
Journal Article
Recenzirano
Odprti dostop
Meeting the challenges brought by the COVID-19 pandemic requires an interdisciplinary approach. In this context, integrating knowledge of immune function with an understanding of how genetic ...variation influences the nature of immunity is a key challenge. Immunogenetics can help explain the heterogeneity of susceptibility and protection to the viral infection and disease progression. Here, we review the knowledge developed so far, discussing fundamental genes for triggering the innate and adaptive immune responses associated with a viral infection, especially with the SARS-CoV-2 mechanisms. We emphasize the role of the HLA and KIR genes, discussing what has been uncovered about their role in COVID-19 and addressing methodological challenges of studying these genes. Finally, we comment on questions that arise when studying admixed populations, highlighting the case of Brazil. We argue that the interplay between immunology and an understanding of genetic associations can provide an important contribution to our knowledge of COVID-19.
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