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Slow rocking chairs can easily put people to sleep, while violent shaking, such as during earthquakes, may lead to rapid awakening. However, the influence of external body vibrations on arousal remains unclear. Herein, a computational model of a locus coeruleus (LC)-norepinephrine (NE) system and cardio-respiratory system were used to show that respiratory entrainment of the LC modulates arousal levels, which is an adaptation to avoid physical risks from external vibration. External vibrations of sinusoidal waves with different frequencies ranging from 0.1 to 20 [Hz] were applied to the LC based on the results of previous studies. We found that respiratory entrainment of the LC decreased the breathing rate (BR) and heart rate (HR) to maintain the HR within its normal range. Furthermore, 1:1 phase locking enhanced arousal level while phase-amplitude coupling decreased it for larger vibration stimuli. These findings suggest that respiratory entrainment of the LC might automatically modulate cardio-respiratory system homeostasis and arousal levels for performance readiness (fight/flight or freeze) to avoid physical risks from larger external vibrations., (© 2023. The Author(s).)

Plutonium (Pu) has been used as a mid-twentieth century time-marker in various geological archives as a result of atmospheric nuclear tests mainly conducted in 1950s. Advancement of analytical techniques allows us to measure 239 Pu and 240 Pu more accurately and can thereby reconstruct the Pacific Pu signal that originated from the former Pacific Proving Grounds (PPG) in the Marshall Islands. Here, we propose a novel method that couples annual banded reef building corals and nearshore anoxic marine sediments to provide a marker to precisely determine the start of the nuclear era which is known as a part of the Anthropocene. We demonstrate the efficacy of the methods using sediment obtained from Beppu Bay, Japan, and a coral from Ishigaki Island, Japan. The sedimentary records show a clear Pu increase from 1950, peaking during the 1960s, and then showing a sharp decline during the 1970s. However, a constantly higher isotope ratio between 239 Pu and 240 Pu suggest an additional contribution other than global fallout via ocean currents. Furthermore, single elevations in 240 Pu/ 239 Pu provide supportive evidence of close-in-fallout similar to previous studies. Coral skeletal radiocarbon displays a clear timing with the signatures supporting the reliability of the Beppu Bay sediments as archives and demonstrates the strength of this method to capture potential Anthropocene signatures., (© 2022. The Author(s).)

PAX2 is a transcription factor essential for kidney development and the main causative gene for renal coloboma syndrome (RCS). The mechanisms of PAX2 action during kidney development have been evaluated in mice but not in humans. This is a critical gap in knowledge since important differences have been reported in kidney development in the two species. In the present study, we hypothesized that key human PAX2-dependent kidney development genes are differentially expressed in nephron progenitor cells from induced pluripotent stem cells (iPSCs) in patients with RCS relative to healthy individuals. Cap analysis of gene expression revealed 189 candidate promoters and 71 candidate enhancers that were differentially activated by PAX2 in this system in three patients with RCS with PAX2 mutations. By comparing this list with the list of candidate Pax2-regulated mouse kidney development genes obtained from the Functional Annotation of the Mouse/Mammalian (FANTOM) database, we prioritized 17 genes. Furthermore, we ranked three genes-PBX1, POSTN, and ITGA9-as the top candidates based on closely aligned expression kinetics with PAX2 in the iPSC culture system and susceptibility to suppression by a Pax2 inhibitor in cultured mouse embryonic kidney explants. Identification of these genes may provide important information to clarify the pathogenesis of RCS, human kidney development, and kidney regeneration.

We newly manufactured miso rich in angiotensin-converting enzyme (ACE) inhibitory activity (Marukome MK-34-1, shinki miso) and investigated its antihypertensive properties in rat models of genetic hypertension. ACE inhibitory activity was tenfold higher in shinki miso than in commercially available Marukome Nenrin miso (nenrin miso). The inhibitory activity of shinki miso was confined to <3 kDa fractions and was detected in several fractions with high polarity by C 18 high-performance liquid chromatography. Systolic blood pressure (SBP) increased age-dependently in stroke-prone spontaneously hypertensive rats (SHRSP/Izm) given a 0.6% (w/v) NaCl solution (salt solution group) that matched the salt content of the miso solutions. This SBP increase was attenuated in both the 5% nenrin and 5% shinki miso solution groups compared to the salt solution group. The reduction in SBP was greater in rats fed shinki than in rats fed nenrin miso. Similarly, in a salt-induced hypertension model with Dahl rats, the 5% nenrin miso solution attenuated the rising SBP observed in the salt solution group. Moreover, combining 5% nenrin miso with 5% shinki miso (2:1, v/v) (awase miso group) significantly decreased the SBP per gram salt intake by 8% compared with the nenrin miso treatment. However, there were no differences in urinary Na excretion between the nenrin and awase miso groups. In conclusion, we produced a new miso with potent ACE inhibitory activity that reduced spontaneous and salt-induced hypertension. These results suggest that salt sensitivity is decreased by the addition of shinki miso to nenrin miso.

Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like (APOBEC) DNA cytosine deaminases have emerged as potential genomic mutators in various cancers. Multiple myeloma accumulates APOBEC signature mutations as it progresses; however, the mechanisms underlying APOBEC signature acquisition and its consequences remain elusive. In this study, we examined the significance and clinical impact of APOBEC3B (A3B) activity in multiple myeloma. Among APOBECs, only highly expressed A3B was associated with poor prognosis in myeloma patients, independent of other known poor prognostic factors. Quantitative PCR revealed that CD138-positive primary myeloma cells and myeloma cell lines exhibited remarkably high A3B expression levels. Interestingly, lentiviral A3B knockdown prevented the generation of deletion and loss-of-function mutations in exogenous DNA, whereas in control cells, these mutations accumulated with time. A3B knockdown also decreased the basal levels of γ-H2AX foci, suggesting that A3B promotes constitutive DNA double-strand breaks in myeloma cells. Importantly, among control shRNA-transduced cells, we observed the generation of clones that harboured diverse mutations in exogenous genes and several endogenous genes frequently mutated in myeloma, including TP53. Taken together, the results suggest that A3B constitutively mutates the tumour genome beyond the protection of the DNA repair system, which may lead to clonal evolution and genomic instability in myeloma.

Adult T-cell leukemia (ATL) is an aggressive T-cell malignancy caused by human T-cell leukemia virus type 1 (HTLV-1). We recently reported that abacavir, an anti-HIV-1 drug, potently and selectively kills ATL cells. This effect was attributed to the reduced expression of tyrosyl-DNA-phosphodiesterase 1 (TDP1), a DNA repair enzyme, in ATL cells. However, the molecular mechanism underlying the downregulation of TDP1 in ATL cells remains elusive. Here we identified the core promoter of the TDP1 gene, which contains a conserved nuclear respiratory factor 1 (NRF-1) binding site. Overexpression of NRF-1 increased TDP1-promoter activity, whereas the introduction of dominant-negative NRF-1 repressed such activity. Overexpression of NRF-1 also upregulated endogenous TDP-1 expression, while introduction of shNRF-1 suppressed TDP1 in Jurkat T cells, making them susceptible to abacavir. These results indicate that NRF-1 is a positive transcriptional regulator of TDP1-gene expression. Importantly, we revealed that HTLV-1 bZIP factor (HBZ) protein which is expressed in all ATL cases physically interacts with NRF-1 and inhibits the DNA-binding ability of NRF-1. Taken together, HBZ suppresses TDP1 expression by inhibiting NRF-1 function in ATL cells. The HBZ/NRF-1/TDP1 axis provides new therapeutic targets against ATL and might explain genomic instability leading to the pathogenesis of ATL.

Mammalian nuclear Dbf2-related (NDR) kinases (LATS1 and 2, NDR1 and 2) play a role in cell proliferation, apoptosis and morphological changes. These kinases are regulated by mammalian sterile 20-like kinases (MSTs) and Mps one binder (MOB) 1. Okadaic acid (OA), which activates MST2, facilitates the complex formation of MOB1, MST2 and NDR1 in HEK293FT cells. The in vitro biochemical study demonstrates the phosphorylation of MOB1 by MST2. The phosphorylated MOB1 alone is capable to partially activate NDR1 in vitro, but MST2 is also required for the full activation. The knockdown of MOB1 or MST2 abolishes the OA-induced NDR1 activation in HEK293FT cells. Among MOB1 mutants, in which each serine or threonine residue is replaced with alanine, MOB1 T74A and T181A mutants fail to activate NDR1. Thr74, but not Thr181, is phosphorylated by MST2 in vitro, although MOB1 is also phosphorylated by MST2 at other site(s). The interaction of MOB1 T74A with NDR1 is barely enhanced by OA treatment. These findings indicate that the phosphorylation of MOB1 at Thr74 by MST2 is essential to make a complex of MOB1, MST2 and NDR1, and to fully activate NDR1.

Junctional adhesion molecule 4 (JAM4) is a cell adhesion molecule that interacts with a tight junction protein, membrane-associated guanylate kinase inverted 1 (MAGI-1). Our previous studies suggest that JAM4 is implicated in the regulation of paracellular permeability and the signalings of hepatocyte growth factor. In this study, we performed yeast two-hybrid screening to search for an unidentified JAM4-binding protein and obtained one isoform of Ligand-of-Numb protein X1 (LNX1), LNXp70, that is an interactor of Numb. Ligand-of-Numb protein X1 is expressed in kidney glomeruli and intestinal epithelial cells, where JAM4 is also detected. Immunoprecipitation from kidney lysates supports the in vivo interaction of proteins. Biochemical studies reveal that JAM4 directly binds the second PDZ domain of LNX1 through its carboxyl terminus. Junctional adhesion molecule 4, LNX1 and Numb form a tripartite complex in vitro and are partially colocalized in heterologous cells. Ligand-of-Numb protein X1 facilitates endocytosis of JAM4 and is involved in transforming growth factor beta -induced redistribution of JAM4 in mammary epithelial cells. Experiments using dominant-negative constructs and RNA interference insure that Numb is necessary for the LNX1-mediated endocytosis of JAM4. All these findings indicate that LNX1 provides an endocytic scaffold for JAM4 that is implicated in the reorganization of cell junctions.

MAGI-1 and CASK are membrane-associated guanylate kinases of epithelial junctions. MAGI-1 is localized at tight junctions in polarized epithelial cells, whereas CASK is localized along the lateral membranes. We obtained the KIAA0769 gene product through the yeast two-hybrid screening using MAGI-1 as a bait and named it Carom. Carom has a coiled-coil domain in the middle region, and two src homology 3 domains and a PSD-95/Dlg-A/ZO-1 (PDZ)-binding motif in the C-terminal region. Carom binds to the fifth PDZ domain of MAGI-1 and the calmodulin kinase domain of CASK in vitro. MAGI-1 and CASK bind to the distinct sequences in the C-terminal region of Carom, but still compete with each other for Carom binding. The study using a stable transformant of Madine Darby canine kidney (MDCK) cells expressing GFP-Carom revealed that Carom was partially overlapped by MAGI-1 in MDCK cells, which have not yet established mature cell junctions, but became separated from MAGI-1 and colocalized with CASK in polarized cells. Carom was highly resistant to Triton X-100 extractions and recruited CASK to the Triton X-100-insoluble structures. Carom is a binding partner of CASK, which interacts with CASK in polarized epithelial cells and may link it to the cytoskeleton.

PAPIN has six PDZ domains and interacts with p0071, a catenin-related protein. Recent studies have revealed that catenins determine the subcellular localization of some PDZ proteins. We have examined whether the localization of PAPIN is determined by p0071 in epithelial cells. PAPIN was localized not only on the lateral membrane but also on the apical membrane, where p0071 was absent. The targeting to both membranes was mediated by the middle region of PAPIN and did not require the p0071-interacting PDZ domain. In cells that came into contact, PAPIN was diffusely distributed on the plasma membrane, while p0071 was concentrated at immature cell-cell contacts. When epithelial cells were exposed to the low concentration of calcium, p0071 was internalized, whereas PAPIN remained on the plasma membrane. We also confirmed that the interaction with p0071 was not essential for the membrane targeting of ERBIN, a recently identified p0071- and ErbB2-binding protein. PAPIN, p0071, and ERBIN formed a complex in 293T cells. Furthermore, ERBIN and ErbB2 were colocalized with PAPIN on the lateral membrane. These findings suggest that PAPIN, p0071, and ERBIN come to the cell-cell contacts independently and interact with each other on the lateral membrane.