No abstract

Aberrant glycosylation is a hallmark of most human cancers and affects many cellular properties, including cell proliferation, apoptosis, differentiation, transformation, migration, invasion, and immune responses. Here, we report that N-acetylgalactosaminyltransferase14 (GALNT14), which mediates the initial step of mucin-type O-glycosylation and is heterogeneously expressed in most breast cancers, plays a critical role in the invasion and migration of breast cancers by regulating the activity of MMP-2 and expression of some EMT genes. We have modulated the expression of GALNT14 by RNAi and overexpression in MCF-7 cells. Overexpression of GALNT14 significantly enhanced cell migration and invasion and promoted the proliferation of breast cancer cells. Knockdown of GALNT14 reduced clonogenicity and attenuates cell migration and cell invasion. The mRNAs for N-cadherin, vimentin, E-cadherin, MMP-2, VEGF, and TGF-β were determined by RT-qPCR involving GALNT14-overexpressing or knockdown MCF-7 cells. Expression profiling revealed the upregulation of N-cadherin, vimentin, MMP-2, VEGF, TGF-β and the downregulation of E-cadherin in GALNT14 overexpressing cells, with the opposite seen in GALNT14 knockdowns. Gelatin zymography analysis further indicated that overexpression of GALNT14 increased MMP-2 activity in MCF-7 cells. Conversely, downregulation of GALNT14 reduced MMP-2 activity. Promoter analysis revealed that GALNT14 stimulates MMP-2 expression through the AP-1-binding site. Western blot analyses showed that knockdown of GALNT14 significantly reduced the expression of an oncoprotein mucin 1 (MUC1). These findings indicate that GALNT14 contributes to breast cancer invasion by altering the cell proliferation, motility, expression levels of EMT genes, and by stimulating MMP-2 activity, suggesting GALNT14 may be a potential target for breast cancer treatment.

The atypical pneumonia caused by SARS-CoV-2 is an ongoing pandemic and a serious threat to global public health. The COVID-19 patients with severe symptoms account for a majority of mortality of this disease. However, early detection and effective prediction of patients with mild to severe symptoms remains challenging. In this study, we performed proteomic profiling of urine samples from 32 healthy control individuals and 6 COVID-19 positive patients (3 mild and 3 severe). We found that urine proteome samples from the mild and severe COVID-19 patients with comorbidities can be clearly differentiated from healthy proteome samples based on the clustering analysis.Multiple pathways have been compromised after the COVID-19 infection, including the dysregulation of immune response, complement activation, platelet degranulation, lipoprotein metabolic process and response to hypoxia.We further validated our finding by directly comparing the same patients' urine proteome after recovery. This study demonstrates the COVID-19 pathophysiology related molecular alterations could be detected in the urine and the potential application of urinary proteome in auxiliary diagnosis, severity determination and therapy development of COVID-19.

Trypsin specifically cleaves the C-terminus of lysine and arginine residues but often fails to cleave modified lysines, such as ubiquitination, therefore resulting in the uncleaved K-ε-GG peptides. Therefore, the cleaved ubiquitinated peptide identification was often regarded as false positives and discarded. Interestingly, unexpected cleavage at the K48-linked ubiquitin chain has been reported, suggesting the latent ability of trypsin to cleave ubiquitinated lysine residues. However, it remains unclear whether other trypsin-cleavable ubiquitinated sites are present. In this study, we verified the ability of trypsin in cleaving K6 and K63 besides K48 chains. The uncleaved K-ε-GG peptide was quickly and efficiently generated during trypsin digestion, whereas cleaved ones were produced with much lower efficiency. Then, the K-ε-GG antibody was proved to efficiently enrich the cleaved K-ε-GG peptides and several published large-scale ubiquitylation datasets were re-analyzed to interrogate the cleaved sequence features. In total, more than 2400 cleaved ubiquitinated peptides were identified in the K-ε-GG and UbiSite antibody-based datasets. The frequency of lysine upstream of the cleaved modified K was significantly enriched. The kinetic activity of trypsin in cleaving ubiquitinated peptides was further elucidated. We suggest that the cleaved K-ε-GG sites with high post-translational modification probability (≥0.75) should be considered as true positives in future ubiquitome analyses.

The ThUBD-HRP probe and the consequential developed TUF-WB+ method can detect polyubiquitination signal through one-step incubation with hypersensitivity, unbiased detection and a shorter operation time compared with the antibody method.

Tissue phenotypic plasticity facilitates rapid adaptation of organisms to biotic and/or abiotic pressure. The reproductive capacity of honey bee workers (Apis mellifera) is plastic and responsive to pheromones produced by broods and the queen. Egg laying workers (ELWs), which could reactivate their ovaries and lay haploid eggs upon queen lost, have been commonly discussed from many aspects. However, it remains unclear whether midgut homeostasis in ELWs is affected during plastic changes. Here, we found that the expression of nutrition- and autophagy-related genes was up-regulated in the midguts of ELWs, compared with that in nurse workers (NWs) by RNA-sequencing. Furthermore, the area and number of autophagosomes were increased, along with significantly increased cell death in the midguts of ELWs. Moreover, cell cycle progression in the midguts of ELWs was increased compared with that in NWs. Consistent with the up-regulation of nutrition-related genes, the body and midgut sizes, and the number of intestinal proliferation cells of larvae reared with royal jelly (RJ) obviously increased more than those reared without RJ in vitro. Finally, cell proliferation was dramatically suppressed in the midguts of ELWs when autophagy was inhibited. Altogether, our data suggested that autophagy was induced and required to sustain cell proliferation in ELWs’ midguts, thereby revealing the critical role of autophagy played in the intestines during phenotypic plasticity changes.

Background Deinococcus radiodurans (D. radiodurans) is best known for its extreme resistance to diverse environmental stress factors, including ionizing radiation (IR), ultraviolet (UV) irradiation, oxidative stress, and high temperatures. Robust DNA repair system and antioxidant system have been demonstrated to contribute to extreme resistance in D. radiodurans. However, practically all studies on the mechanism underlying D. radiodurans’s extraordinary resistance relied on the treated strain during the post-treatment recovery lag phase to identify the key elements involved. The direct gene or protein changes of D. radiodurans after stress have not yet been characterized. Results In this study, we performed a proteomics profiling on D. radiodurans right after the heavy ion irradiation treatment, to discover the altered proteins that were quickly responsive to IR in D. radiodurans. Our study found that D. radiodurans shown exceptional resistance to 12C6+ heavy ion irradiation, in contrast to Escherichia coli (E.coli) strains. By using iTRAQ (Isobaric Tags for Relative and Absolute Quantitation)-based quantitative mass spectrometry analysis, the kinetics of proteome changes induced by various dosages of 12C6+ heavy ion irradiation were mapped. The results revealed that 452 proteins were differentially expressed under heavy ion irradiation, with the majority of proteins being upregulated, indicating the upregulation of functional categories of translation, TCA cycle (Tricarboxylic Acid cycle), and antioxidation regulation under heavy ion irradiation. Conclusions This study shows how D. radiodurans reacts to exposure to 12C6+ heavy ion irradiation in terms of its overall protein expression profile. Most importantly, comparing the proteome profiling of D. radiodurans directly after heavy ion irradiation with research on the post-irradiation recovery phase would potentially provide a better understanding of mechanisms underlying the extreme radioresistance in D. radiodurans.