Highlights d Numerous SARS-CoV-2 proteins synergize to suppress immune sensing and signaling d Nsp14 targets IFNAR1 for lysosomal degradation d ORF3a and ORF7a block autophagy by different mechanisms d Synergistic treatment with IFN-g and -l1 is highly effective against SARS-CoV-2

20Higher-order chromosome folding and segregation is tightly regulated in all domains 21 of life. In bacteria, details on nucleoid organization regulatory mechanisms and function 22 remains poorly characterized, especially in non-model species. Here, we investigate 23 the role of DNA partitioning protein ParB and condensin complexes, two key players 24 in bacterial chromosome structuring, in the actinobacterium Corynebacterium 25 glutamicum. Chromosome conformation capture reveals SMC-mediated long-range 26 interactions around ten centromere-like parS sites clustered at the replication origin 27 (oriC). At least one oriC-proximal parS site is necessary for a reliable chromosome 28 segregation. Using a combination of chromatin immunoprecipitation and 29 photoactivated single molecule localization microscopy evidences the formation of 30 distinct ParB-nucleoprotein subclusters in dependence of parS numbers. We further 31 identified and functionally characterized two condensin paralogs. Whereas 32 SMC/ScpAB complexes are loaded via ParB at parS sites mediating chromosomal 33 inter-arm contacts like in Bacillus subtilis, the MukBEF-like SMC complex MksBEFG 34 does not contribute to chromosomal DNA-folding. Rather, the MksBEFG complex is 35 involved in plasmid maintenance and interacts with the polar oriC-tethering factor 36 DivIVA. These data complement current models of ParB-SMC/ScpAB crosstalk, while 37 showing that some condensin complexes evolved functions uncoupled from 38 chromosome folding. 39 Keywords 40 ParB, parS, SMC, MksB, condensin, actinobacteria, chromosome conformation 41 capture, chromatin immunoprecipitation, super-resolution microscopy, DNA 42 segregation 43 44 can cause severe DNA segregation phenotypes 18,19 . To date, only few studies 71 investigated the impact of chromosomal parS localization on DNA-segregation and 72 folding 18-22 . 73 In addition to ParABS systems, most bacteria harbor condensin complexes, members 74 of the structural maintenance of chromosomes (SMC) family of proteins found in all 75 kingdoms of life 23 . In standard model organisms, condensins are equally essential for 76 faithful chromosome segregation by compacting DNA into separate nucleoids 24-26 . The 77 SMC/ScpAB (structural maintenance of chromosomes) complex is well-studied in B. 78 subtilis, where it consists of two large SMC subunits and the kleisin ScpA associated 79 with dimeric accessory protein ScpB that assemble into a ring-like structure 27 . A recent 80 study suggests progressive extrusion of condensin-encircled DNA loops upon 81 conformational changes in the SMC subunit, which leads to a gradual size increase of 82 trapped DNA molecules 28 . The active process(es) driving DNA extrusion 29,30 allow(s) 83 for translocation along the chromosome with velocities of around 50 Kb/ min 31 , and 84 depend(s) on the ATPase activity of SMC 32 . To be loaded on parS sites, SMC/ScpAB 85 complexes necessitate ParB 20,22,33,34 . They redistribute to distant chromosomal 86 regions, promoting topological changes, and notab...

Alteration of epigenetic modifications plays an important role in human cancer. Notably, the dysregulation of histone post-translational modifications (PTMs) has been associated with several cancers including colorectal cancer (CRC). However, the signature of histone PTMs on circulating nucleosomes is still not well described. We have developed a fast and robust enrichment method to isolate circulating nucleosomes from plasma for further downstream proteomic analysis. This method enabled us to quantify the global alterations of histone PTMs from 9 CRC patients and 9 healthy donors. Among 54 histone proteoforms identified and quantified in plasma samples, 13 histone PTMs were distinctive in CRC. Notably, methylation of histone H3K9 and H3K27, acetylation of histone H3 and citrullination of histone H2A1R3 were upregulated in plasma of CRC patients. A comparative analysis of paired samples identified 3 common histone PTMs in plasma and tumor tissue including the methylation and acetylation state of lysine 27 of histone H3. Moreover, we highlight for the first time that histone H2A1R3 citrulline is a modification upregulated in CRC patients. This new method presented herein allows the detection and quantification of histone variants and histone PTMs from circulating nucleosomes in plasma samples and could be used for biomarker discovery of cancer.

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