A Putative Calcium-Permeable Cyclic Nucleotide-Gated Channel, CNGC18, Regulates Polarized Pollen Tube Growth

A tip-focused Ca^2＋ gradient is tightly coupled to polarized pollen tube growth, and tip-localized influxes of extracellular Ca^2＋ are required for this process. However the molecular identity and regulation of the potential Ca^2＋ channels remains elusive. The present study has implicated CNGC18 （cyclic nucleotide-gated channel 18） in polarized pollen tube growth, because its overexpression induced wider and shorter pollen tubes. Moreover, CNGC18 overexpression induced depolarization of pollen tube growth was suppressed by lower extracellular calcium （[Ca^2＋]ex）. CNGC18-yellow fluorescence protein （YFP） was preferentially localized to the apparent post-Golgi vesicles and the plasma membrane （PM） in the apex of pollen tubes. The PM localization was affected by tip-localized ROP1 signaling. Expression of wild type ROP1 or an active form of ROP1 enhanced CNGC18-YFP localization to the apical region of the PM, whereas expression of RopGAP1 （a ROP1 deactivator） blocked the PM localization. These results support a role for PM-Iocalized CNGC18 in the regulation of polarized pollen tube growth through its potential function in the modulation of calcium influxes.     

Agrobacterium-mediated transformation of apple (Malus x domestica Borkh.): an assessment of factors affecting regeneration of transgenic plants

We have previously developed a protocol for efficient gene transfer and regeneration of transgenic calli following cocultivation of apple (cv. Jonagold) explants with Agrobacterium tumefaciens (De Bondt et al. 1994, Plant Cell Reports 13: 587–593). Now we report on the optimization of postcultivation conditions for efficient and reproducible regeneration of transgenic shoots from the apple cultivar Jonagold. Factors which were found to be essential for efficient shoot regeneration were the use of gelrite as a gelling agent and the use of the cytokinin-mimicing thidiazuron in the selective postcultivation medium. Improved transformation efficiencies were obtained by combining the hormones thidiazuron and zeatin and by using leaf explants from in vitro grown shoots not older than 4 weeks after multiplication. Attempts to use phosphinothricin acetyl transferase as a selectable marker were not successful. Using selection on kanamycin under optimal postcultivation conditions, about 2% of the leaf explants developed transgenic shoots or shoot clusters. The presence and expression of the transferred genes was verified by -glucuronidase assays and Southern analysis. The transformation procedure has also been succesfully applied to several other apple cultivars.Abbreviations BAP benzylaminopurine - CTAB hexadecyltrimethylammoniumbromide - Na₂EDTA ethylenediamine-tetra-acetate ferric-sodium salt - FeNaEDTA ethylenediamine-tetra-acetate ferric-sodium salt - GA₃ gibberellic acid 3 - GusA -glucuronidase - gusA -glucuronidase gene of Escherichia coli - IAA indole acetic acid - IBA indole butyric acid - 2iP N6-2-isopentenyl adenine - NAA naphthalene acetic acid - nptII neomycinphosphotransferase II gene - bar phosphinothricin acetyl transferase gene - PCR polymerase chain reaction - PPT phosphinothricin - STS silver thiosulphate - T-DNA transferred DNA - TDZ thidiazuron - X-Gluc 5-bromo-4-chloro-3-indolyl -D-glucuronide - Zea trans-Zeatin     

Distinct basolateral amygdala excitatory inputs mediate the somatosensory and aversive-affective components of pain

Pain is a multidimensional perception that includes unpleasant somatosensory and affective experiences; however, the underlying neural circuits that mediate different components of pain remain elusive. Although hyperactivity of basolateral amygdala glutamatergic (BLA^Glu) neurons is required for the somatosensory and emotional processing of pain, the precise excitatory inputs to BLA^Glu neurons and their roles in mediating different aspects of pain are unclear. Here, we identified two discrete glutamatergic neuronal circuits in male mice: a projection from the insular cortex glutamatergic (IC^Glu) to BLA^Glu neurons, which modulates both the somatosensory and affective components of pain, and a projection from the mediodorsal thalamic nucleus (MD^Glu) to BLA^Glu neurons, which modulates only the aversive-affective component of pain. Using whole-cell recording and fiber photometry, we found that neurons within the IC→BLA and MD→BLA pathways were activated in mice upon inflammatory pain induced by injection of complete Freund’s adjuvant (CFA) into their paws. Optical inhibition of the IC^Glu→BLA pathway increased the nociceptive threshold and induced behavioral place preference in CFA mice. In contrast, optical inhibition of the MD^Glu→BLA pathway did not affect the nociceptive threshold but still induced place preference in CFA mice. In normal mice, optical activation of the IC^Glu→BLA pathway decreased the nociceptive threshold and induced place aversion, while optical activation of the MD^Glu→BLA pathway only evoked aversion. Taken together, our results demonstrate that discrete IC^Glu→BLA and MD^Glu→BLA pathways are involved in modulating different components of pain, provide insights into its circuit basis, and better our understanding of pain perception.     

Local Recurrence of Soft Tissue Sarcoma Revisited: Is there a Role for “Selective” Radiation?

BackgroundRadiation therapy (RT) is often utilized in cases of high-grade soft tissue sarcoma (STS), but there remain situations where treatment is with surgical excision alone. Our goals were to determine (1) the local recurrence (LR) rate with and without perioperative RT and (2) associations between local recurrence, patient, tumor, and treatment variables.MethodsWe performed a retrospective review of 165 consecutive STS patients. A Cox proportional hazards model was used to investigate variables associated with local recurrence.ResultsLR occurred in 15/78 (19%) without RT, 4/29 (14%) with postoperative RT, and 0/58 with preoperative RT (p=0.002). We found increased rates of local recurrence at 24 months for myxofibrosarcoma (p=0.001) and no-RT (p=0.003). Myxofibrosarcoma accounted for 33 (20%) of the study patients and 12 (63%) of the local recurrences.ConclusionThe LR rate in patients treated with surgery alone was disproportionately attributable to myxofibrosarcoma (11/23 cases, 48%). Other subtypes demonstrated a lower rate of LR in the absence of RT (4/55 cases, 7%), and no LR occurred when final margins were >2 mm. In certain circumstances treatment with a negative margin surgical resection followed by close observation is justifiable. RT is effective and should continue to be considered routinely in myxofibrosarcoma or when surgical margins are inadequate. Level of Evidence: III     

一株广谱中和抗原性出血热病毒株的发现

一株分离自杭州市褐家鼠的出血热病毒Gou_3株的免疫血清对10株I型病毒的中和滴度除二株为160外均为320,而对4株Ⅱ型病毒的滴度为320—640,说明Gou_3株免疫血清对两型毒株中和效价大多数无差异或只差2倍,是一株中和抗原广谱的毒株。用I型和Ⅱ型毒株免疫血清对Gou_3株进行型别检定结果表明Gou_3株是Ⅱ型病毒。     

Mitochondrial dysfunction leads to reduced chronological lifespan and increased apoptosis in yeast

We previously isolated a Saccharomyces cerevisiae mutant (HsTnII), which displays 40% reduced chronological lifespan as compared to the wild type (WT). In this study, we found HsTnII cultures to be characterized by fragmented and dysfunctional mitochondria, and by increased initiation of apoptosis during chronological aging as compared to WT. Expression of genes encoding subunits of mitochondrial electron transport chain and ATP synthase is significantly downregulated in HsTnII, and as a consequence, HsTnII is not able to respire ethanol. All these data confirm the importance of functional mitochondria and respiration in determining yeast chronological lifespan and apoptosis.