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Tracking virus infection in plants is useful to assess plant susceptibility or resistance. The recombinant cucumber mosaic virus (CMV) expressing a 2b-fused green fluorescent protein (GFP, 25 kDa) gradually loses (within weeks) the GFP gene in plants. Here, we constructed CMV expressing a flavin-based small fluorescent protein (iLOV, 10 kDa). CMV-iLOV still retains iLOV after 28 dpi in upper leaves of inoculated Nicotiana benthamiana and allows long-term monitoring of its distribution in plants. Using CMV-iLOV, we showed that pot1, a recessive allele for resistance to potyviruses, does not confer CMV resistance in tomato. [ABSTRACT FROM AUTHOR]

In Bangladesh, citrus is an important fruit crop that is becoming more commonly cultivated in commercial plantations. In March 2019, we observed yellowing, vein clearing, and mild mosaic symptoms in citron (Citrus medica). Based on systematic serological and molecular analyses of the symptomatic leaf samples, the Citrus tristeza virus (CTV) was identified. To the best of our knowledge, this is the first report of CTV and any citrus virus in Bangladesh. [ABSTRACT FROM AUTHOR]

Leaf blotting to detect proteins and investigate their spatial distribution in leaves has so far mainly been used to detect viral coat proteins that accumulate abundantly in infected leaves, but rarely to detect endogenous plant proteins. We improved the method for detecting endogenous proteins. We found that microperforating leaves with bundled pins before blotting, then pressing leaves with a rolling pin onto polyvinylidene difluoride (PVDF) membranes enabled even blotting of sap. This microperforated leaf blotting (mPLB) was also suitable for use with nylon membranes to detect leaf RNA. The mPLB revealed that accumulation of two endogenous proteins, calmodulin-like rgs-CaM and actin, was respectively positively and negatively associated with that of viral coat protein in tobacco leaves infected with cucumber mosaic virus (CMV). When a tobacco plant primed with benzothiadiazole was inoculated with CMV, mPLB showed that the infection was restricted to some areas of the leaf and that in these areas the mRNA encoding tobacco pathogenesis-related protein 1, an indicator of salicylic acid-mediated immune responses, was induced. These results demonstrate the effectiveness of mPLB for investigating the spatial distribution of endogenous and viral gene expression in leaves. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate prognostic factors including efficacy of postoperative chemotherapy in Japanese patients with uterine carcinosarcoma. Methods: We conducted a retrospective survey of seven medical facilities in the Tohoku Gynecologic Cancer Unit. Results: A total of 45 patients who had undergone hysterectomy and bilateral salpingo-oophorectomy were enrolled. No significant difference was observed in overall survival according to patient age (≤50 years vs >50 years) or retroperitoneal lymphadenectomy (performed vs. not performed). However, the International Federation of Gynecology and Obstetrics stage (stage I/II vs stage III/IV) and postoperative chemotherapy (provided vs not provided) were significant prognostic factors in both univariate and multivariate analyses for the 25-month median follow-up period. Conclusions: Our results revealed that postoperative chemotherapy should be considered for all uterine carcinosarcoma stages in Japanese patients. [ABSTRACT FROM AUTHOR]

Background: Paclitaxel and carboplatin (PC) have shown antitumor activity in carcinosarcoma of the uterus (CS). The purpose of this prospective multi-institutional study was to determine the response rate (RR), progression-free survival (PFS) and overall survival (OS) and to assess the toxicity of paclitaxel and carboplatin in patients with CS. Methods: We conducted a phase II study in which patients were administered paclitaxel 175 mg/m over a 3-h period followed by carboplatin (area under the serum concentration-time curve = 6) intravenously over a 30-min period on day 1 of each treatment cycle (3 weeks) until disease progression or adverse effects prohibited further therapy. Eligible patients had histologically confirmed, advanced stage (III or IV), persistent or recurrent measurable disease, and no prior chemotherapy. Results: Six patients were enrolled between February 2006 and April 2009. The median age of the patients was 61 (range 48-77) years; one patient was stage IIIC (17 %) and five were stage IVB (83 %). Three patients (50 %) (1 at stage IIIC and 2 at stage IVB) received total abdominal hysterectomy plus bilateral salpingo-oophorectomy as part of the initial treatment; five (83 %) had homologous tumors and one (17 %) had a heterologous tumor. The median cycle number administered was 4.8 (range 2-7). The RR was 66.7 % (complete response, 2; partial response, 2); the PFS was 9.1 months and OS was not reached. The frequently observed Grade 4 toxicities were neutropenia (3 patients, 50 %). Manageable neutropenic sepsis developed in one patient. Conclusion: This is the first prospective multi-institutional study in Asia showing that PC may be effective and tolerable for the treatment of advanced or recurrent CS. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s13314-022-00457-z. Correction to: Australasian Plant Disease Notes (2022) 17:12 https://doi.org/10.1007/s13314-0... The wrong Supplementary file was originally published with this article; it has now been replaced with the correct file. [Extracted from the article]

Two recessive resistance genes against Clover yellow vein virus (ClYVV), cyv1 and cyv2, have been previously reported. We recently screened resistant peas from a separate set of pea lines and classified them into two groups according to their distinct modes of resistance. We later revealed that one group carries cyv2, encoding eukaryotic translation initiation factor 4E (eIF4E), in linkage group (LG) VI. We explored the possibility that the resistance gene, tentatively designated non- cyv2, that confers resistance to the other group, was actually cyv1. We found that PI 236493, which carries cyv1, had restricted cell-to-cell movement of ClYVV similar to that in non- cyv2 peas including PI 429853. PI 429853 was crossed with susceptible line PI 250438. Mapping of F progeny revealed that non- cyv2 was 4 cM from the simple sequence repeat marker AB40, whose loci are close to cyv1, mo, and sbm- 2 mapped in LG II, which mediates resistance to other potyviruses. Moreover, PI 429853 crossed with PI 236493 produced F progeny resistant to ClYVV, raising the possibility that non- cyv2 is allelic to cyv1. Because mo was previously mapped with eIF( iso) 4E in LG II, we examined the possibility that non- cyv2, cyv1, and mo encoded eIF(iso)4E. However, there was no difference in the nucleotide sequence of the eIF(iso)4E-coding region between susceptible and resistant pea lines. The eIF( iso) 4E gene was equivalently expressed in both PI 429853 and PI 250438 before and after ClYVV infection. Our results suggest that these resistance genes are unlikely to encode eIF(iso)4E on LG II. [ABSTRACT FROM AUTHOR]

Many plant viruses encode suppressors of RNA silencing, including the helper component-proteinase (HC-Pro) of potyviruses. Our previous studies showed that a D-to-Y mutation at amino acid position 193 in HC-Pro (HC-Pro-D193Y) drastically attenuated the virulence of clover yellow vein virus (ClYVV) in legume plants. Furthermore, RNA-silencing suppression (RSS) activity of HC-Pro-D193Y was significantly reduced in Nicotiana benthamiana. Here, we examine the effect of expression of heterologous suppressors of RNA silencing, i.e., tomato bushy stunt virus p19, cucumber mosaic virus 2b, and their mutants, on the virulence of the ClYVV point mutant with D193Y (Cl-D193Y) in pea. P19 and 2b fully and partially complemented Cl-D193Y multiplication and virulence, including lethal systemic HR in pea, respectively, but the P19 and 2b mutants with defects in their RSS activity did not. Our findings strongly suggest that the D193Y mutation exclusively affects RSS activity of HC-Pro and that RSS activity is necessary for ClYVV multiplication and virulence in pea. [ABSTRACT FROM AUTHOR]

Double-stranded RNAs formed in secondary structures and replicative intermediates of viral genomes are thought to strongly elicit RNA silencing. This phenomenon is known as virus-induced gene silencing (VIGS). VIGS is a powerful tool for modifying gene expression in host plants. We constructed a virus vector based on White clover mosaic virus (WClMV) and demonstrated VIGS of phytoene desaturase (PDS) in pea. Photobleaching of tissues, caused by VIGS of PDS, was observed in restricted areas of upper leaves and stems. We confirmed that the PDS mRNA and subgenomic RNAs of WClMV were reduced in the photobleached tissues. [ABSTRACT FROM AUTHOR]

Small RNAs direct RNA-induced silencing complexes (RISCs) to regulate stability and translation of mRNAs. RISCs associated with target mRNAs often accumulate in discrete cytoplasmic foci known as GW-bodies. However, RISC proteins can associate with membrane compartments such as the Golgi and endoplasmic reticulum. Here, we show that GW-bodies are associated with late endosomes (multivesicular bodies, MVBs). Blocking the maturation of MVBs into lysosomes by loss of the tethering factor HPS4 (ref. 5) enhances short interfering RNA (siRNA)- and micro RNA (miRNA)-mediated silencing in Drosophila melanogaster and humans. It also triggers over-accumulation of GW-bodies. Blocking MVB formation by ESCRT (endosomal sorting complex required for transport) depletion results in impaired miRNA silencing and loss of GW-bodies. These results indicate that active RISCs are physically and functionally coupled to MVBs. We further show that MVBs promote the competence of RISCs in loading small RNAs. We suggest that the recycling of RISCs is promoted by MVBs, resulting in RISCs more effectively engaging with small RNA effectors and possibly target RNAs. It may provide a means to enhance the dynamics of RNA silencing in the cytoplasm. [ABSTRACT FROM AUTHOR]

The same mutant allele of eukaryotic initiation factor 4E ( eIF4E) that confers resistance to Pea seed-borne mosaic virus ( sbm-1) and the white lupine strain of Bean yellow mosaic virus ( wlv) also confers resistance to Clover yellow vein virus (ClYVV) in pea. The eIF4E genes from several pea lines were isolated and sequenced. Analysis of the eIF4E amino acid sequences from several resistant lines revealed that some lines, including PI 378159, have the same sequence as reported for sbm-1 and wlv. When eIF4E from a susceptible pea line was expressed from a ClYVV vector after mechanical inoculation of resistant PI 378159, the virus caused systemic infection, similar to its effects in susceptible line PI 250438. The resistance to ClYVV in line PI 378159 was characterized through a cross with PI 193835, which reportedly carries cyv-2. Mechanical inoculation of the F1 progeny with ClYVV resulted in no infection, indicating that the resistance gene in PI 378159 is identical to cyv-2 in PI 193835. Furthermore, particle bombardment of pea line PI 193835 with infectious cDNA of ClYVV (pClYVV/C3-S65T) resulted in the same resistance mode as that described for PI 378159. These results demonstrate that the resistance to ClYVV conferred by cyv-2 is mediated by eIF4E and that cyv-2 is identical to sbm-1 and wlv. [ABSTRACT FROM AUTHOR]

Ti-30mass%Mo alloy is characterized by far better corrosion resistance than pure titanium in non-oxidizing acid such as 35% HC1 solution. This alloy was newly developed in this work by a powder metallurgical process, because the conventional melting-casting process had difficulties in manufacturing the alloy owing to its heavy gravity segregation. The corrosion behavior of sintered Ti-30Mo alloy was studied by both immersion test and electro-chemical measurement. The corrosion rate of 1.3X10−2[mm/yearxxx] was obtained by immersion test in 35% HC1 solution, which was 103 times superior to that of pure titanium. The potentio-dynamic polarization curve of this alloy in 35% HC1 solution showed more noble corrosion potential and lower anodic current density than those of pure titanium. The passive film formed on the alloy, in which Mo was enriched by preferential dissolution of titanium, thought to suppress the anodic reaction and improve its corrosion resistance. [ABSTRACT FROM AUTHOR]

A correction to the article "Silencing by Small RNAs Is Linked to Endosomal Trafficking," that was published online in the August 16, 2009 issue is presented.