Melatonin-priming ameliorates aluminum accumulation and toxicity in rice through enhancing aluminum exclusion and maintaining redox homeostasis.

Seed priming can effectively enhance the plant's ability to withstand stress during subsequent growth and development; however, the role of melatonin-priming in attenuating aluminum (Al) toxicity remain unknown. In this study, 10, 50 and 100 μM melatonin were selected for rice seed priming to investigate the protective effects and potential mechanisms of melatonin against Al toxicity. Al stress inhibited seed germination by induction of abscisic acid (ABA) accumulation and reduction of α-amylase activity.

Coupling of SK channels, L-type Ca channels, and ryanodine receptors in cardiomyocytes.

Small-conductance Ca-activated K (SK) channels regulate the excitability of cardiomyocytes by integrating intracellular Ca and membrane potentials on a beat-to-beat basis. The inextricable interplay between activation of SK channels and Ca dynamics suggests the pathology of one begets another. Yet, the exact mechanistic underpinning for the activation of cardiac SK channels remains unaddressed.

Action Potential Shortening and Impairment of Cardiac Function by Ablation of .

Background: Intracellular pH (pH) is critical to cardiac excitation and contraction; uncompensated changes in pH impair cardiac function and trigger arrhythmia. Several ion transporters participate in cardiac pH regulation. Our previous studies identified several isoforms of a solute carrier Slc26a6 to be highly expressed in cardiomyocytes.

Calmodulin activation of polo-like kinase 1 is required during mitotic entry.

Polo-like kinase 1 (Plk1) is a conserved key regulator of the G2/M transition, but its upstream spatiotemporal regulators remain unknown. With the help of immunofluorescence, co-immunoprecipitation, and glutathione S-transferase (GST) pull-down assay, we found that calmodulin (CaM) is one such regulatory molecule that associates with Plk1 from G2 to metaphase. More importantly, this interaction results in considerable stimulation of Plk1 kinase activity leading to hyperphosphorylation of Cdc25C.

Meeting report: fungal its workshop (october 2012).

This report summarizes a meeting held in Boulder, CO USA (19-20 October 2012) on fungal community analyses using ultra-high-throughput sequencing of the internal transcribed spacer (ITS) region of the nuclear ribosomal RNA (rRNA) genes. The meeting was organized as a two-day workshop, with the primary goal of supporting collaboration among researchers for improving fungal ITS sequence resources and developing recommendations for standard ITS primers for the research community.

Calmodulin bound to stress fibers but not microtubules involves regulation of cell morphology and motility.

Calmodulin (CaM) is a major cytoplasmic calcium receptor that performs multiple functions including cell motility. To investigate the mechanism of the regulation of CaM on cell morphology and motility, first we checked the distribution of CaM in the living cells using GFP-CaM as an indicator. We found that GFP-CaM showed a fiber-like distribution pattern in the cytosol of living Potorous tridactylis kidney (PtK2) cells but not in living HeLa cells.

Calmodulin is essential for angiogenesis in response to hypoxic stress in endothelial cells.

Angiogenesis, the formation of new blood vessels that is regulated by hypoxia, is a critical process for the growth and spread of tumors. Multiple phases of this process, including migration, adhesion, and formation of new capillary tubes, are needed for optimal tumor growth. Here, a new regulatory function for Ca2+-CaM in the vascular endothelium is described.

Polo-like kinase 1 regulates mitotic arrest after UV irradiation through dephosphorylation of p53 and inducing p53 degradation.

Ultraviolet (UV) irradiation can result in cell cycle arrest. The reactivation of Polo-like kinase 1 (Plk1) is necessary for cell cycle reentry. But the mechanism of how Plk1 regulates p53 in UV-induced mitotic arrest cells remained elusive.

Knockdown of c-Met by adenovirus-delivered small interfering RNA inhibits hepatocellular carcinoma growth in vitro and in vivo.

c-Met is highly expressed and constitutively activated in various human tumors. We employed adenovirus-mediated RNA interference technique to knock down c-Met expression in hepatocellular carcinoma cells and observed its effects on hepatocellular carcinoma cell growth in vitro and in vivo. Among the five hepatocellular carcinoma and one normal human liver cell lines we analyzed, c-Met was highly expressed and constitutively tyrosine phosphorylated in only MHCC97-L and HCCLM3 hepatocellular carcinoma cells.

Calmodulin regulates the post-anaphase reposition of centrioles during cytokinesis.

A transient postanaphase repositioning of the centriole is found to control the completion of cytokinesis. Using a green fluorescent protein-calmodulin fusion protein as a living cell probe, we have previously found that calmodulin is associated with the initiation and progression of cytokinesis. In this study, we further studied the effect of calmodulin on the repositioning of the centriole and subsequent cell cycle progression.

[Study on the role of calcium signal during mature resumption of isolated mouse germinal vesicles in a cell free system].

A cell-free system including HeLa cell lysate of synchronized metaphase or G2-phase and isolated germinal vesicles (GV) from mouse oocytes was used to study the role of calcium and its downstream mediator during mature resumption. The isolated GVs could resume meiotic maturation in the lysate prepared from M phase HeLa cell, which marked by chromatin condensation. And this process was not affected by calcium chelating agent.

The association of calmodulin with central spindle regulates the initiation of cytokinesis in HeLa cells.

Calmodulin is a major cytoplasmic calcium receptor that performs multiple functions in the cell including cytokinesis. Central spindle appears between separating chromatin masses after metaphase-anaphase transition. The interaction of microtubules from central spindle with cell cortex regulates the cleavage furrow formation.

Spatiotemporal pattern of calmodulin and [Ca2+]i is related to resumption of meiosis in mouse oocytes.

During meiotic maturation, mammalian oocytes undergo a series of morphological and physiological changes that prepare them for fertilization. Calcium-initiated signaling is thought to trigger these processes. In this study, we examine the spatio-temporal pattern of calcium and calmodulin (CaM), its downstream receptor, in order to investigate their association with meiotic maturation.

[The distribution of calmodulin with midbody and its involvement in cytokinesis regulation].

Calmodulin (CaM) is a major cytoplasmic Ca2+ receptor and performs a multiplicity of functions in the cell. By using GFP-CaM fusion protein, we have studied the detailed dynamic redistribution of CaM during cytokinesis in HeLa cells. CaM associates with midbody in late cytokinesis phase.