The Msd1–Wdr8–Pkl1 complex anchors microtubule minus ends to fission yeast spindle pole bodies

The minus ends of spindle microtubules are anchored to a microtubule-organizing center. The conserved Msd1/SSX2IP proteins are localized to the spindle pole body (SPB) and the centrosome in fission yeast and humans, respectively, and play a critical role in microtubule anchoring. In this paper, we show that fission yeast Msd1 forms a ternary complex with another conserved protein, Wdr8, and the minus end–directed Pkl1/kinesin-14. Individual deletion mutants displayed the identical spindle-protrusion phenotypes. Msd1 and Wdr8 were delivered by Pkl1 to mitotic SPBs, where Pkl1 was tethered through Msd1–Wdr8. The spindle-anchoring defect imposed by msd1/wdr8/pkl1 deletions was suppressed by a mutation of the plus end–directed Cut7/kinesin-5, which was shown to be mutual. Intriguingly, Pkl1 motor activity was not required for its anchoring role once targeted to the SPB. Therefore, spindle anchoring through Msd1–Wdr8–Pkl1 is crucial for balancing the Cut7/kinesin-5–mediated outward force at the SPB. Our analysis provides mechanistic insight into the spatiotemporal regulation of two opposing kinesins to ensure mitotic spindle bipolarity.This research was supported by Cancer Research UK (T. Toda)

The conserved Wdr8-hMsd1/SSX2IP complex localises to the centrosome and ensures proper spindle length and orientation

The centrosome plays a pivotal role in a wide range of cellular processes and its dysfunction is causally linked to many human diseases including cancer and developmental and neurological disorders. This organelle contains more than one hundred components, and yet many of them remain uncharacterised. Here we identified a novel centrosome protein Wdr8, based upon the structural conservation of the fission yeast counterpart. We showed that Wdr8 constitutively localises to the centrosome and super resolution microscopy uncovered that this protein is enriched at the proximal end of the mother centriole. Furthermore, we identified hMsd1/SSX2IP, a conserved spindle anchoring protein, as one of Wdr8 interactors by mass spectrometry. Wdr8 formed a complex and partially colocalised with hMsd1/SSX2IP. Intriguingly, knockdown of Wdr8 or hMsd1/SSX2IP displayed very similar mitotic defects, in which spindle microtubules became shortened and misoriented. Indeed, Wdr8 depletion resulted in the reduced recruitment of hMsd1/SSX2IP to the mitotic centrosome, though the converse is not true. Together, we propose that the conserved Wdr8-hMsd1/SSX2IP complex plays a critical role in controlling proper spindle length and orientation.T.T. and A.P.S were supported by Cancer Research UK.Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.bbrc.2015.10.169

Abyssal fauna of the UK-1 polymetallic nodule exploration area, Clarion-Clipperton Zone, central Pacific Ocean: Mollusca

The file attached is the Published/publisher’s pdf version of the article. This is an OpenAccess article.Copyright Helena Wiklund et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Left in the cold? Evolutionary origin of Laternula elliptica a keystone bivalve species of Antarctic benthos

The large, burrowing bivalve Laternula elliptica is an abundant component of shallow-water soft-substrate communities around Antarctica but its congeners are temperate and tropical in distribution and their phylogenetic relationships are obscure. A new molecular analysis of Laternulidae species shows that there are two distinct clades, one of Exolaternula species, E. spengleri and E. liautaudi, possessing a ligamental lithodesma and a larger clade of species lacking the lithodesma. Of the latter, Laternula elliptica is a sister taxon to temperate and tropical species, including those that live around the coasts of Australia from Tasmania to Darwin. It is suggested that L. elliptica was left isolated around Antarctica following the opening of the Tasman Gateway and initiation of the Circum-Antarctic Current as Australia drifted northwards following the final breakup of Gondwana. A further scenario is that as Australia moved closer to Asia, species spread into tropical habitats and more widely to the Red Sea and Japan. Exolaternula species have a likely Tethyan origin and the present-day range is from the Arabian Gulf, around southern Asia and as far north as southern Russia

Extracellular High Mobility Group Box 1 Plays a Role in the Effect of Bone Marrow Mononuclear Cell Transplantation for Heart Failure

Transplantation of unfractionated bone marrow mononuclear cells (BMCs) repairs and/or regenerates the damaged myocardium allegedly due to secretion from surviving BMCs (paracrine effect). However, donor cell survival after transplantation is known to be markedly poor. This discrepancy led us to hypothesize that dead donor BMCs might also contribute to the therapeutic benefits from BMC transplantation. High mobility group box 1 (HMGB1) is a nuclear protein that stabilizes nucleosomes, and also acts as a multi-functional cytokine when released from damaged cells. We thus studied the role of extracellular HMGB1 in the effect of BMC transplantation for heart failure. Four weeks after coronary artery ligation in female rats, syngeneic male BMCs (or PBS only as control) were intramyocardially injected with/without anti-HMGB1 antibody or control IgG. One hour after injection, ELISA showed that circulating extracellular HMGB1 levels were elevated after BMC transplantation compared to the PBS injection. Quantitative donor cell survival assessed by PCR for male-specific sry gene at days 3 and 28 was similarly poor. Echocardiography and catheterization showed enhanced cardiac function after BMC transplantation compared to PBS injection at day 28, while this effect was abolished by antibody-neutralization of HMGB1. BMC transplantation reduced post-infarction fibrosis, improved neovascularization, and increased proliferation, while all these effects in repairing the failing myocardium were eliminated by HMGB1-inhibition. Furthermore, BMC transplantation drove the macrophage polarization towards alternatively-activated, anti-inflammatory M2 macrophages in the heart at day 3, while this was abolished by HMGB1-inhibition. Quantitative RT-PCR showed that BMC transplantation upregulated expression of an anti-inflammatory cytokine IL-10 in the heart at day 3 compared to PBS injection. In contrast, neutralizing HMGB1 by antibody-treatment suppressed this anti-inflammatory expression. These data suggest that extracellular HMGB1 contributes to the effect of BMC transplantation to recover the damaged myocardium by favorably modulating innate immunity in heart failure

New molecular phylogeny of Lucinidae: increased taxon base with focus on tropical Western Atlantic species (Mollusca: Bivalvia)

Taylor, John D., Glover, Emily A., Smith, Lisa, Ikebe, Chiho, Williams, Suzanne T. (2016): New molecular phylogeny of Lucinidae: increased taxon base with focus on tropical Western Atlantic species (Mollusca: Bivalvia). Zootaxa 4196 (3): 381-398, DOI: http://doi.org/10.11646/zootaxa.4196.3.

Unexpected species diversity within Sri Lanka's snakehead fishes of the Channa marulius group (Teleostei: Channidae)

Sudasinghe, Hiranya, Adamson, Eleanor A. S., Ranasinghe, R.H. Tharindu, Meegaskumbura, Madhava, Ikebe, Chiho, Britz, Ralf (2020): Unexpected species diversity within Sri Lanka's snakehead fishes of the Channa marulius group (Teleostei: Channidae). Zootaxa 4747 (1): 113-132, DOI: 10.11646/zootaxa.4747.1.

Channa ara

<i>Channa ara</i> (Deraniyagala, 1945) <p>(Figure 2,3)</p> <p> <i>Ophicephalus marulius ara</i>: Deraniyagala, 1945: 95; Deraniyagala, 1952: 124 (in part)</p> <p> <i>Ophiocephalus marulius</i> (not Hamilton, 1822): Day, 1878: 363 (in part); Day, 1889: 360 (in part)</p> <p> <i>Ophicephalus marulius</i>: Deraniyagala, 1929: 83 (in part)</p> <p> <i>Channa marulius</i>: Pethiyagoda, 1991: 279 (in part); Talwar & Jhingran, 1991: 1017 (in part); Courtenay & Williams, 2004: 83 (in part); Chaudhry, 2010 (in part); Kottelat, 2013: 461 (in part)</p> <p> <i>Channa ara</i>: Pethiyagoda, 2006 (in part)</p> <p> <b>Diagnosis.</b> <i>Channa ara</i> is distinguished from <i>C. marulius</i>, <i>C. aurolineata</i> and <i>C. auroflammea</i> by possessing fewer vertebrae (56 vs 59–63 in <i>C. marulius</i>; 63–66 in <i>C. aurolineata</i>; 58–61 in <i>C. auroflammea</i>); fewer lateral-line scales (59–62 vs 62–65 in <i>C. marulius</i>; 65–71 in <i>C. aurolineata</i>; 61–65 in <i>C. auroflammea</i>); fewer dorsal-fin rays (47–48 vs 50–56 in <i>C. marulius</i>; 55–58 in <i>C. aurolineata</i>; 52–54 in <i>C. auroflammea</i>); and fewer anal-fin rays (29–30 vs 32–37 in <i>C. marulius</i>; 35–38 in <i>C. aurolineata</i>; 33–36 in <i>C. auroflammea</i>). Further, <i>C. ara</i> can be distinguished from <i>C. aurolineata</i> and <i>C. marulioides</i> by white spots along mid-lateral blotches faint or absent (vs series of black scales rimmed in white along the mid-lateral dark blotches) in live adults. In comparison to South Indian <i>C. pseudomarulius</i>, <i>C. ara</i> possesses more vertebrae (56 vs 55); and more circumpeduncular scales (26–28 vs 24). <i>Channa ara</i> can be distinguished from <i>C.</i> cf. <i>ara</i> from the southwestern wet zone of Sri Lanka by having more circumpeduncular scales (26–28 vs 22–24); by the absence / faintness of the numerous large white spots along the mid-lateral dark blotches (vs. presence of spots in <i>C.</i> cf. <i>ara</i>); and by bright orange colouration in between the mid-lateral series of dark brown blotches when live (vs white to yellow colouration) (see Figures 2–5).</p> <p> <b>Description.</b> See Figures 2 and 3 for general appearance, and Tables 1 and 2 for morphometric and meristic data, respectively. Dorsal-fin rays 47 (1), or 48 (2). Anal-fin rays 29 (2), or 30 (1). Pectoral-fin rays 16. Lateral line scales 59 (1), 60 (1), or 62 (1) in total, 16 (1), 17 (1), or 18 (1) in pre-drop, 2 (1), or 3 (2) forming drop, 40 (1), or 41 (2) in post-drop. Predorsal scales 17 (2), or 18 (1). Scales above pre-drop 4.5 (2), or 5 (1), above post-drop 6.5 (1), 7 (1), or 7.5 (1), below post-drop 10 (2), or 11 (1). Circumpeduncular scales 26 (1) or 28 (2). Postorbital scales 10 (1), 11 (1), or 12 (1), with 7 (2), or 8 (1) scales in front of opercle; scales on opercle 3 (1), or 4 (2). Vertebrae 56 (Fig. 6A).</p> <p> <b>Colouration in preservative.</b> Shortly after preservation, adults> 300 mm SL (Figure 2) with head and body greyish dorsolaterally, white ventrally. Dorsal, anal, and caudal fins black with scattered white spots. Pectoral fin dark brown, pelvic fin white. Series of 4–6 large black blotches on mid-lateral body under dorsal fin, separated by bright orange blotches. White spots on body inconspicuous or absent. Orange blotches on body fading to white during long-term preservation.</p> <p> <b>Colouration in life.</b> Juveniles of about 80–100 mm SL (Fig. 3A) dorsolaterally brown. A black band on side of body, originating at anterior margin of snout, extending to caudal-fin base and beyond, onto median rays of caudal fin. Light brown stripe extending from opercle to caudal-fin base, separating brown dorsal side and blackish ventral side of body. Head and body whitish cream ventrally. Caudal fin with an ocellus on dorsal half, formed by large black spherical spot rimmed by wide orange ring. Pectoral, pelvic and anal fins hyaline. Interradial membrane of dorsal fin with irregular pattern of black lines. Pupil outlined by yellowish orange rim, iris black with tinge of orange.</p> <p>Adults> 500 mm SL (Fig. 3B) greyish black dorso-laterally. Black blotches on mid-lateral body, separated by bright orange blotches, extending as a ventro-lateral band along head and body. White spots on head and body absent or indistinct. Ocellus on caudal fin absent. Pupil outlined by yellowish orange rim, iris orange. Dorsal, anal and caudal fins black with white spots. Pectoral fin brownish black; rays of pelvic fin darker than in smaller specimens.</p> <p> <b>Habitat, distribution and natural history.</b> <i>Channa ara</i> occurs primarily in the deep pools in the Mahaweli River and its tributaries. It has also been recorded from reservoirs in the Mahaweli catchment (Victoria and Randenigala: Fig. 1A). In June 2014, the first author observed around 20 juveniles of ~ 80–100 mm SL in shallow water (~ 60–80 cm deep), among submerged roots, close to the bank, at the mouth of a stream draining into Badulu Oya of the Mahaweli basin, they were guarded by a pair of adults. The highest elevation from which we have recorded <i>C. ara</i> is at Kandy, about 500 m asl.</p> <p> <b>Molecular results.</b> Three <i>cox1</i> haplotypes were observed among Marulius group fishes collected in Sri Lanka, none of which have previously been observed in fishes collected in neighbouring continental regions. The three haplotypes correspond to <i>Channa ara</i> from the Mahaweli Basin (H1, <i>n</i> =4), <i>C.</i> cf. <i>ara</i> from the southwestern wet zone (H2, <i>n</i> =8), and <i>C. marulius</i> from the northern dry zone (H3, <i>n</i> =1). The relationship of Sri Lankan haplotypes to <i>C. marulius</i> haplotypes from continental regions (India and Myanmar) is illustrated in Fig. 1B, with uncorrected pairwise genetic distances among all members of the Marulius group given in Table 3.</p> <p> The <i>Channa ara cox 1</i> haplotype differs from all [<i>C. marulius</i> + <i>C.</i> cf. <i>ara</i>] haplotypes by a minimum of 22 mutations, and is indeed marginally more genetically similar to continental <i>C. marulius</i> (3.6–4.2%) and Sri Lankan <i>C.</i> cf. <i>ara</i> (3.7%) than to Sri Lankan <i>C. marulius</i> (4.6%), albeit the latter was only represented by a small sample size. The Sri Lankan <i>C. marulius</i> differs from continental <i>C. marulius</i> by 1.6–2.3%, doubling the known intraspecific genetic divergence at <i>cox1</i> that was previously observed across this species’ large continental geographical distribution encompassing India and western Myanmar. In contrast, the Sri Lankan <i>C.</i> cf. <i>ara</i> differs less from continental <i>C. marulius</i> (uncorrected pairwise genetic distance of 1.0–1.6%) than it does from the <i>C. marulius</i> that occurs on the same island, in Sri Lanka’s northern dry zone (2.0%).</p> <p> With the exceptions of <i>Channa marulius</i> and <i>C.</i> cf. <i>ara</i>, <i>C. ara</i> differs from all other species in the Marulius group by a minimum of 8% uncorrected pairwise genetic distance for <i>cox1</i> (Table 3).</p>Published as part of <i>Sudasinghe, Hiranya, Adamson, Eleanor A. S., Ranasinghe, R. H. Tharindu, Meegaskumbura, Madhava, Ikebe, Chiho & Britz, Ralf, 2020, Unexpected species diversity within Sri Lanka's snakehead fishes of the Channa marulius group (Teleostei: Channidae), pp. 113-132 in Zootaxa 4747 (1)</i> on pages 116-119, DOI: 10.11646/zootaxa.4747.1.4, <a href="http://zenodo.org/record/3693477">http://zenodo.org/record/3693477</a&gt