The rapid development of digital platform businesses has facilitated the expansion of gig work in China and elsewhere in recent years. Now that IT-powered platforms have been used in part to free the ...capital from taking employer responsibilities, the capital’s toolkit for labor control has been significantly limited. Drawing on qualitative field research supplemented by quantitative data on Uber in China, this article provides a novel empirical account of the labor control of digital platforms, and more importantly, their effects on different types of workers. The authors have identified three crucial strategies that Uber has devised to control its drivers’ labor process: an incentive pay system, a customer evaluation system, and flexible work arrangements. These strategies will, however, demonstrate significant effects on drivers’ working hours and income only when we consider the different motivations of Uber drivers. Specifically, the working efforts of those who drive for Uber as their only source of income are responsive to incentive pay schemes and a platform’s evaluation system, but are not as responsive to work flexibility. The exact opposite is the case for drivers who have other jobs and sources of income.
The arms race between entomopathogenic bacteria and their insect hosts is an excellent model for decoding the intricate coevolutionary processes of host-pathogen interaction. Here, we demonstrate ...that the MAPK signaling pathway is a general switch to trans-regulate differential expression of aminopeptidase N and other midgut genes in an insect host, diamondback moth (Plutella xylostella), thereby countering the virulence effect of Bacillus thuringiensis (Bt) toxins. Moreover, the MAPK cascade is activated and fine-tuned by the crosstalk between two major insect hormones, 20-hydroxyecdysone (20E) and juvenile hormone (JH) to elicit an important physiological response (i.e. Bt resistance) without incurring the significant fitness costs often associated with pathogen resistance. Hormones are well known to orchestrate physiological trade-offs in a wide variety of organisms, and our work decodes a hitherto undescribed function of these classic hormones and suggests that hormonal signaling plasticity is a general cross-kingdom strategy to fend off pathogens.
Liquid biopsy has been rapidly developed in recent years due to its advantages of non-invasiveness and real-time sampling in cancer prognosis and diagnosis. Exosomes are nanosized extracellular ...vesicles secreted by all types of cells and abundantly distributed in all types of body fluid, carrying diverse cargos including proteins, DNA, and RNA, which transmit regulatory signals to recipient cells. Among the cargos, exosomal proteins have always been used as immunoaffinity binding targets for exosome isolation. Increasing evidence about the function of tumor-derived exosomes and their proteins is found to be massively associated with tumor initiation, progression, and metastasis in recent years. Therefore, exosomal proteins and some nucleic acids, such as miRNA, can be used not only as targets for exosome isolation but also as potential diagnostic markers in cancer research, especially for liquid biopsy. This review will discuss the existing protein-based methods for exosome isolation and characterization that are more appropriate for clinical use based on current knowledge of the exosomal biogenesis and function. Additionally, the recent studies for the use of exosomal proteins as cancer biomarkers are also discussed and summarized, which might contribute to the development of exosomal proteins as novel diagnostic tools for liquid biopsy.
Host-pathogen interactions are central components of ecological networks where the MAPK signaling pathways act as central hubs of these complex interactions. We have previously shown that an insect ...hormone modulated MAPK signaling cascade participates as a general switch to
trans
-regulate differential expression of diverse midgut genes in the diamondback moth,
Plutella xylostella
(L.) to cope with the insecticidal action of Cry1Ac toxin, produced by the entomopathogenic bacterium
Bacillus thuringiensis
(Bt). The relationship between topology and functions of this four-tiered phosphorylation signaling cascade, however, is an uncharted territory. Here, we carried out a genome-wide characterization of all the MAPK orthologs in
P
.
xylostella
to define their phylogenetic relationships and to confirm their evolutionary conserved modules. Results from quantitative phosphoproteomic analyses, combined with functional validations studies using specific inhibitors and dsRNAs lead us to establish a MAPK “road map”, where p38 and ERK MAPK signaling pathways, in large part, mount a resistance response against Bt toxins through regulating the differential expression of multiple Cry toxin receptors and their non-receptor paralogs in
P
.
xylostella
midgut. These data not only advance our understanding of host-pathogen interactions in agricultural pests, but also inform the future development of biopesticides that could suppress Cry resistance phenotypes.
Insecticidal crystal toxins derived from the soil bacterium Bacillus thuringiensis (Bt) are widely used as biopesticide sprays or expressed in transgenic crops to control insect pests. However, ...large-scale use of Bt has led to field-evolved resistance in several lepidopteran pests. Resistance to Bt Cry1Ac toxin in the diamondback moth, Plutella xylostella (L.), was previously mapped to a multigenic resistance locus (BtR-1). Here, we assembled the 3.15 Mb BtR-1 locus and found high-level resistance to Cry1Ac and Bt biopesticide in four independent P. xylostella strains were all associated with differential expression of a midgut membrane-bound alkaline phosphatase (ALP) outside this locus and a suite of ATP-binding cassette transporter subfamily C (ABCC) genes inside this locus. The interplay between these resistance genes is controlled by a previously uncharacterized trans-regulatory mechanism via the mitogen-activated protein kinase (MAPK) signaling pathway. Molecular, biochemical, and functional analyses have established ALP as a functional Cry1Ac receptor. Phenotypic association experiments revealed that the recessive Cry1Ac resistance was tightly linked to down-regulation of ALP, ABCC2 and ABCC3, whereas it was not linked to up-regulation of ABCC1. Silencing of ABCC2 and ABCC3 in susceptible larvae reduced their susceptibility to Cry1Ac but did not affect the expression of ALP, whereas suppression of MAP4K4, a constitutively transcriptionally-activated MAPK upstream gene within the BtR-1 locus, led to a transient recovery of gene expression thereby restoring the susceptibility in resistant larvae. These results highlight a crucial role for ALP and ABCC genes in field-evolved resistance to Cry1Ac and reveal a novel trans-regulatory signaling mechanism responsible for modulating the expression of these pivotal genes in P. xylostella.
ABC transporter superfamily is one of the largest and ubiquitous groups of proteins. Because of their role in detoxification, insect ABC transporters have gained more attention in recent years. In ...this study, we annotated ABC transporters from a newly sequenced sweetpotato whitefly genome. Bemisia tabaci Q biotype is an emerging global invasive species that has caused extensive damages to field crops as well as ornamental plants.
A total of 55 ABC transporters containing all eight described subfamilies (A to H) were identified in the B. tabaci Q genome, including 8 ABCAs, 3 ABCBs, 6 ABCCs, 2 ABCDs, 1 ABCE, 3 ABCFs, 23 ABCGs and 9 ABCHs. In comparison to other species, subfamilies G and H in both phloem- and blood-sucking arthropods are expanded. The temporal expression profiles of these 55 ABC transporters throughout B. tabaci developmental stages and their responses to imidacloprid, a neonicotinoid insecticide, were investigated using RNA-seq analysis. Furthermore, the mRNA expression of 24 ABC transporters (44% of the total) representing all eight subfamilies was confirmed by the quantitative real-time PCR (RT-qPCR). Furthermore, mRNA expression levels estimated by RT-qPCR and RNA-seq analyses were significantly correlated (r = 0.684, p < 0.01).
It is the first genome-wide analysis of the entire repertoire of ABC transporters in B. tabaci. The identification of these ABC transporters, their temporal expression profiles during B. tabaci development, and their response to a neonicotinoid insecticide lay the foundation for functional genomic understanding of their contribution to the invasiveness of B. tabaci.
Accurate evaluation of gene expression requires normalization relative to the expression of reliable reference genes. Expression levels of "classical" reference genes can differ, however, across ...experimental conditions. Although quantitative real-time PCR (qRT-PCR) has been used extensively to decipher gene function in the sweetpotato whitefly Bemisia tabaci, a world-wide pest in many agricultural systems, the stability of its reference genes has rarely been validated.
In this study, 15 candidate reference genes from B. tabaci were evaluated using two Excel-based algorithms geNorm and Normfinder under a diverse set of biotic and abiotic conditions. At least two reference genes were selected to normalize gene expressions in B. tabaci under experimental conditions. Specifically, for biotic conditions including host plant, acquisition of a plant virus, developmental stage, tissue (body region of the adult), and whitefly biotype, ribosomal protein L29 was the most stable reference gene. In contrast, the expression of elongation factor 1 alpha, peptidylprolyl isomerase A, NADH dehydrogenase, succinate dehydrogenase complex subunit A and heat shock protein 40 were consistently stable across various abiotic conditions including photoperiod, temperature, and insecticide susceptibility.
Our finding is the first step toward establishing a standardized quantitative real-time PCR procedure following the MIQE (Minimum Information for publication of Quantitative real time PCR Experiments) guideline in an agriculturally important insect pest, and provides a solid foundation for future RNA interference based functional study in B. tabaci.
To characterize the clinical features of IgG4-related disease (IgG4-RD) in China.
A prospective cohort study of IgG4-RD was carried out in Peking Union Medical College Hospital between 2011 and 2013. ...Patients with newly diagnosed IgG4-RD were enrolled.
A total of 118 patients with IgG4-RD were enrolled, including 82 males and 36 females, aged 53.1 (s.d. 13.6) years. The most common symptom at onset was lacrimal gland swelling (38/32.2%). A range of organs were involved: 77 patients (65.3%) had lymphadenopathy, 76 (64.4%) had sialadenitis, 60 (50.8%) had dacryoadenitis, 45 (38.1%) had autoimmune pancreatitis, 32 (27.1%) had pulmonary involvement, 31 (26.3%) had periaortitis/retroperitoneal fibrosis, 29 (35.4% of male patients) had prostatitis and 29 (24.6%) had renal involvement. In addition, there were 21 (17.8%) cases of sclerosing cholangitis, 15 (12.7%) of sinusitis and 10 (8.5%) of inflammatory pseudotumour. Uncommon manifestations included mediastinal fibrosis, skin involvement, sclerosing thyroiditis, hypophysitis, orchitis and colitis. Multiple organ involvement was observed in 93 patients, whereas only 4.2% had only a single organ involved. A history of allergy was reported in 73 (61.9%) patients. The serum IgG4 level was elevated in 97.5% and was correlated with the number of organs involved. Most patients were treated with glucocorticoids alone or in combination with immunosuppressive drugs, and the majority usually improved within 3 months.
IgG4-RD is a systemic inflammatory and sclerosing disease. Parotid and lacrimal involvement (formerly called Mikulicz's disease), lymphadenopathy and pancreatitis are the most common manifestations. Patients with IgG4-RD showed favourable responses to treatment with glucocorticoids and immunosuppressive agents.
Vegetation suitability assessment is the premise of scientific vegetation restoration and identifying its effect factors is conducive to imposing more targeted measures. In this paper, we take 24 ...social-economic factors that may affect vegetation suitability as indicators and construct the three criterion layers of production, life and policy. Then, we use cross-sectional data of 448 counties in the Yellow River Basin during 2018 to analyze how the social-economic factors influence the vegetation suitability. The results show that human activity factors affecting vegetation suitability vary a lot for counties in different reaches of the Yellow River. To be specific, overirrigation and overfertilization have negative influences on vegetation suitability in upstream counties. In the middle reaches, development of the secondary industry and urbanization have the most significant negative effects on vegetation suitability. When it comes to the lower reaches, economic advance contributes to the vegetation suitability, but an excessive population density counteracts this positive effect. We also find that the implementation of major ecological projects has played a positive role in improving vegetation suitability in the last few years, and the more targeted the policies are, the more significant their effects will be. In summary, there is no doubt that overfrequent human activities can interfere with the vegetation suitability. At the end of this article, we put forward some pertinent suggestions on how to better play the subjective initiative of human activities to improve the suitability of vegetation.
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