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561.
Chikashi Toyoshima 《The EMBO journal》2009,28(12):1782-1791
Heavy metal pumps constitute a large subgroup in P‐type ion‐transporting ATPases. One of the outstanding features is that the nucleotide binding N‐domain lacks residues critical for ATP binding in other well‐studied P‐type ATPases. Instead, they possess an HP‐motif and a Gly‐rich sequence in the N‐domain, and their mutations impair ATP binding. Here, we describe 1.85 Å resolution crystal structures of the P‐ and N‐domains of CopA, an archaeal Cu+‐transporting ATPase, with bound nucleotides. These crystal structures show that CopA recognises the adenine ring completely differently from other P‐type ATPases. The crystal structure of the His462Gln mutant, in the HP‐motif, a disease‐causing mutation in human Cu+‐ATPases, shows that the Gln side chain mimics the imidazole ring, but only partially, explaining the reduction in ATPase activity. These crystal structures lead us to propose a role of the His and a mechanism for removing Mg2+ from ATP before phosphoryl transfer. 相似文献
562.
Shimoda T Kishimoto H Takabayashi J Amano H Dicke M 《Experimental & applied acarology》2009,47(2):111-120
Anti-predator defenses provided by complex webs of Tetranychus mites can severely impede the performance of generalist predatory mites, whereas this may not be true for specialist predatory
mites. Although some specialist predatory mites have developed morphological protection to reduce the adverse effects of complex
webs, little is known about their behavioral abilities to cope with the webs. In this study, we compared thread-cutting behavior
of three specialist predatory mites, Phytoseiulus persimilis, Neoseiulus
womersleyi and N. californicus, exhibited inside the complex web of T. urticae. No major difference was observed among them in the basic pattern of this behavior, using chelicerae and palps, and in the
number of silken threads severed while moving inside the web. These results and observations suggest that each predator species
cut many sticky silken threads to move inside the complex web without suffering from serious obstruction.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
563.
Takeshi Shimoda 《Experimental & applied acarology》2010,50(1):9-22
Herbivore-induced plant volatiles (HIPVs) emitted from lima bean leaves infested with the two-spotted spider mites Tetranychus urticae strongly attract the predatory mites Neoseiulus californicus. Among these HIPVs, methyl salicylate and linalool can attract the predators. Three green-leaf volatiles (GLVs) of (Z)-3-hexen-1-ol, (Z)-3-hexenyl acetate and (E)-2-hexenal, found in the odor blends from T. urticae-infested leaves and physically damaged leaves, can also attract the predators. To search for a strong predator attractant,
the olfactory responses of N. californicus to each synthetic compound or their combinations were investigated in a Y-tube olfactometer. When presented a choice between
a mixture of the five compounds (i.e. the two HIPVs and the three GLVs) and T. urticae-infested leaves, N. californicus did not discriminate between these odor sources. The same trend was observed when either a mixture of the two HIPVs or methyl
salicylate vs. T. urticae-infested leaves were compared. In contrast, the predators preferred T. urticae-infested leaves to linalool, each of the three GLVs, or a mixture of the three GLVs. These results indicated that methyl
salicylate is a strong predator attractant, and its potential attractiveness almost equaled that of the blend of HIPVs from
T. urticae-infested leaves. 相似文献
564.
Shimoda H 《Histochemistry and cell biology》2009,131(2):231-238
The cellular expression of Angiopoietin-2 (Ang2) was studied during lymphatic development in mouse by immunohistochemistry
and compared to that of lymphatic endothelial markers. At the earliest stage of lymphvasculogenesis, Prox1-identified lymphatic
precursor cells of the cardinal vein displayed an intense immunoreaction for Ang2 in their cytoplasm, implying that Ang2 may
adjust lymphatic specification and sprouting from the veins under the control of Prox1. Thereafter, Ang2 was constantly expressed
in Prox1 and/or LYVE-1-immunopositive endothelial cells of lymphatic sacs and vessels, ranging from lymphatic capillaries
to collectors, throughout embryonic and neonatal development, and the lymphatic endothelial cells simultaneously exhibited
immunoreactivity to Tie2, a primary receptor for angiopoietins. These results suggest that lymphatic endothelial cells may
regulate lymphatic development via their own Ang2-Tie2 signaling. Ang2 is further immunolocalized in the developing blood
vessels including hepatic sinusoids, adrenal medullary vasculature and postnatal pulmonary vessels, thereby indicating that
the blood vessels, which undergo vascular remodeling and sudden alteration of blood flow during the development, are also
likely to express Ang2. The present study is first to demonstrate Ang2 expression in the lymphatic endothelial cells during
development, and consequently Ang2 is regarded as a molecular profile of the developing lymphatic endothelial cells required
for lymphatic vascular organization. 相似文献
565.
566.
A novel gene trs1 in the fission yeast Schizosaccharomyces pombe has been genetically defined. The trs1 mutant showed several intriguing phenotypes. Cells were sensitive to starvation and rapidly lost viability in the stationary phase; cells in the stationary phase were sensitive to heat shock. Some heat-shock proteins were not induced and the heat-shock response in log-phase cells was defective. These mutant phenotypes strongly suggest a vital function of the trs1 gene product for transition from the G1 to G0 phase on starvation and for the normal heat-shock response. 相似文献
567.
568.
569.
Seung Jin Kim Yoshiaki Sota Yasuto Naoi Keiichiro Honma Naofumi Kagara Tomohiro Miyake Masafumi Shimoda Tomonori Tanei Shigeto Seno Hideo Matsuda Shinzaburo Noguchi Kenzo Shimazu 《Translational oncology》2021,14(2)
Recent studies demonstrated that homologous repair deficiency (HRD) score is a useful marker for response to poly (ADP-ribose) polymerase inhibitors or platinum-based chemotherapy. We determined HRD scores and elucidated the clinicopathologic characteristics of HRD-high tumors and their response to non-platinum-based chemotherapy. Primary breast cancer patients (n = 120) were pre-operatively treated with paclitaxel followed by 5-fluorouracil/epirubicin/cyclophosphamide (P-FEC). Germline and somatic homologous recombination related gene mutations (gHRRm and sHRRm, respectively) and HRD scores were analyzed using whole exome sequencing (WES) in tumor tissues obtained before chemotherapy. Of 120 tumors, 30 were determined to be HRD-high tumors, significantly associated with high Ki-67 (P = 0.014), ER negativity (P = 0.007), and PR negativity (P = 0.021). Triple-negative cancers showed significantly higher HRD scores than the luminal, luminal-HER2, and HER2 subtypes (P = 0.023, 0.016, and 0.033, respectively). HRD scores were significantly higher in tumors with gHRRm than in those with sHRRm (P = 0.002) or wild-type HRR genes (P = 1.44e-4), but no significant difference was found in HRD scores between tumors with sHRRm and wild-type HRR genes (P = 0.206). HRD-high tumors had significantly (P = 0.003) higher pCR rates and higher near-pCR rates (P = 0.049) compared with those of the HRD-low tumors in all tumors and the luminal subtype, respectively. HRD-high tumors were associated with aggressive phenotypes and gHRRm, but not sHRRm. Our findings suggested that HRD scores might be useful in predicting response to P-FEC in the luminal subtype. 相似文献
570.