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Serological screening and detection of genomic RNA indicates that members of the genus Henipavirus are present not only in Southeast Asia but also in African fruit bats. We demonstrate that the surface glycoproteins F and G of an African henipavirus (M74) induce syncytium formation in a kidney cell line derived from an African fruit bat, Hypsignathus monstrosus . Despite a less broad cell tropism, the M74 glycoproteins show functional similarities to glycoproteins of Nipah virus.

Summary In all eukaryotic cells, correct segregation of the genetic material during cell division requires proper positioning and alignment of the mitotic spindle with respect to the cell division plane. In the fission yeast Schizosaccharomyces pombe , the spindle is aligned by interphase microtubules during early mitosis [1], and by astral microtubules and cell shape during late mitosis [2]. However, the mechanisms that control spindle alignment in mid-mitosis are not known. The lack of such a control could lead to extensive spindle rotation and misalignment, which, in turn, would result in chromosome mis-segregation if spindle elongation were impaired [1]. Here, we show that the association of mitochondria with the spindle poles reduces spindle rotation. In wild-type cells, spindles with associated mitochondria did not rotate as much as free spindles. In a mutant lacking the centrosomin-related protein Mto1p, the association between mitochondria and spindles was reduced and the spindles rotated more than those in wild-type cells. We propose that there is a symbiotic relationship between mitochondria and the mitotic spindle, in which close association between the two organelles facilitates the positioning of both: while the spindle helps to segregate mitochondria equally among the nascent daughter cells [3], mitochondria decrease spindle rotation and thus promote spindle alignment.

SARS-CoV-2, the cause of the COVID-19 pandemic, exploits host cell proteins for viral entry into human lung cells. One of them, the protease TMPRSS2, is required to activate the viral spike protein (S). Even though two inhibitors, camostat and nafamostat, are known to inhibit TMPRSS2 and block cell entry of SARS-CoV-2, finding further potent therapeutic options is still an important task. In this study, we report that a late-stage drug candidate, otamixaban, inhibits SARS-CoV-2 cell entry. We show that otamixaban suppresses TMPRSS2 activity and SARS-CoV-2 infection of a human lung cell line, although with lower potency than camostat or nafamostat. In contrast, otamixaban inhibits SARS-CoV-2 infection of precision cut lung slices with the same potency as camostat. Furthermore, we report that otamixaban's potency can be significantly enhanced by (sub-) nanomolar nafamostat or camostat supplementation. Dominant molecular TMPRSS2-otamixaban interactions are assessed by extensive 109 μs of atomistic molecular dynamics simulations. Our findings suggest that combinations of otamixaban with supplemental camostat or nafamostat are a promising option for the treatment of COVID-19., SARS-CoV-2, the cause of the COVID-19 pandemic, exploits host proteins for viral entry into human lung cells and is blocked by otamixaban in combination with a covalent protease inhibitor.