A Networked Sensor System for the Analysis of Plot-Scale Hydrology.

This study presents the latest updates to the Audubon Society of Western Pennsylvania (ASWP) testbed, a $50,000 USD, 104-node outdoor multi-hop wireless sensor network (WSN). The network collects environmental data from over 240 sensors, including the EC-5, MPS-1 and MPS-2 soil moisture and soil water potential sensors and self-made sap flow sensors, across a heterogeneous deployment comprised of MICAz, IRIS and TelosB wireless motes. A low-cost sensor board and software driver was developed for communicating with the analog and digital sensors. Innovative techniques (e.g., balanced energy efficient routing and heterogeneous over-the-air mote reprogramming) maintained high success rates (>96%) and enabled effective software updating, throughout the large-scale heterogeneous WSN. The edaphic properties monitored by the network showed strong agreement with data logger measurements and were fitted to pedotransfer functions for estimating local soil hydraulic properties. Furthermore, sap flow measurements, scaled to tree stand transpiration, were found to be at or below potential evapotranspiration estimates. While outdoor WSNs still present numerous challenges, the ASWP testbed proves to be an effective and (relatively) low-cost environmental monitoring solution and represents a step towards developing a platform for monitoring and quantifying statistically relevant environmental parameters from large-scale network deployments.

Reduction of Saccharomyces cerevisiae Pom34 protein level by SESA network is related to membrane lipid composition.

Various pathways block initiation of translation of the bulk of mRNAs in response to membrane stress, amino acid starvation and unfolded proteins. In contrast, SESA, a network of proteins comprising Smy2, Eap1, Scp160 and Asc1, is a novel inhibitor of translation initiation of specific mRNAs. SESA binds POM34 mRNA in response to failure in spindle pole body (SPB) duplication process and inhibits its initiation of translation. We herein report that Pom34 protein level is reduced also in cells with altered membrane lipid composition upon treatment with various chemicals and show that SESA-induced downregulation of Pom34 is crucial for viability of cells with a disturbed nuclear envelope. Thus, we propose that SESA's action in SPB duplication process is dependent on the alteration of membrane lipid composition to facilitate the insertion process.

Dual Role of an mps-2/KCNE-Dependent Pathway in Long-Term Memory and Age-Dependent Memory Decline.

Activity-dependent persistent changes in neuronal intrinsic excitability and synaptic strength are underlying learning and memory. Voltage-gated potassium (Kv) channels are potential regulators of memory and may be linked to age-dependent neuronal disfunction. MinK-related peptides (MiRPs) are conserved transmembrane proteins modulating Kv channels; however, their possible role in the regulation of memory and age-dependent memory decline are unknown. Here, we show that, in C. elegans, mps-2 is the sole member of the MiRP family that controls exclusively long-term associative memory (LTAM) in AVA neuron. In addition, we demonstrate that mps-2 also plays a critical role in age-dependent memory decline. In young adult worms, mps-2 is transcriptionally upregulated by CRH-1/cyclic AMP (cAMP)-response-binding protein (CREB) during LTAM, although the mps-2 baseline expression is CREB independent and instead, during aging, relies on nhr-66, which acts as an age-dependent repressor. Deletion of nhr-66 or its binding element in the mps-2 promoter prevents age-dependent transcriptional repression of mps-2 and memory decline. Finally, MPS-2 acts through the modulation of the Kv2.1/KVS-3 and Kv2.2/KVS-4 heteromeric potassium channels. Altogether, we describe a conserved MPS-2/KVS-3/KVS-4 pathway essential for LTAM and also for a programmed control of physiological age-dependent memory decline.

Telomere-led meiotic chromosome movements: recent update in structure and function.

In S. cerevisiae prophase meiotic chromosomes move by forces generated in the cytoplasm and transduced to the telomere via a protein complex located in the nuclear membrane. We know that chromosome movements require actin cytoskeleton [13,31] and the proteins Ndj1, Mps3, and Csm4. Until recently, the identity of the protein connecting Ndj1-Mps3 with the cytoskeleton components was missing. It was also not known the identity of a cytoplasmic motor responsible for interacting with the actin cytoskeleton and a protein at the outer nuclear envelope. Our recent work [36] identified Mps2 as the protein connecting Ndj1-Mps3 with cytoskeleton components; Myo2 as the cytoplasmic motor that interacts with Mps2; and Cms4 as a regulator of Mps2 and Myo2 interaction and activities (Figure 1). Below we present a model for how Mps2, Csm4, and Myo2 promote chromosome movements by providing the primary connections joining telomeres to the actin cytoskeleton through the LINC complex.

Spindle pole body duplication defective yeast cells are more prone to membrane damage.

Correct separation of chromosomes during mitosis is essential for preventing genetic instability and aneuploidy. Such separation is dependent on correct duplication of the nuclear-associated microtubular organizing center, i.e., spindle pole body (SPB), in fungi. MonoPolar Spindle 2 (MPS2) is an essential gene, encoding a membrane protein required for the insertion of SPB into the nuclear envelope. We recently reported that the SESA complex, which is composed of Smy2, Eap1, Scp160, and Asc1, suppresses the essential role of MPS2 (Sezen et al. 2009, Genes & Development 23:1559-1570), i.e., in SESA-active cells Mps2 becomes nonessential. We also proposed that the SESA network facilitates this insertion by altering the membrane lipid composition (Sezen 2015, FEMS Yeast Research 15:fov089). In addition, we are interested in the antifungal properties of essential oils and previously reported that membrane integrity of yeast cells is impaired upon exposure to turpentine, thyme, oregano, and orange peel essential oils (Konuk and Ergüden 2017, BioCell 41:13-18). Due to our continuing interest in the SESA system and the mechanisms by which essential oils affect yeast cells, we aimed to investigate the effects of essential oils on yeast cell membranes. Herein, we show that mps2∆ 2µm-SMY2 and mps2∆ pom34∆ cells, in which the SESA complex is active and SPB duplication is defective, are more prone to membrane damage upon treatment with essential oils.

Reliability of a commercially available heterochromatic flicker photometer, the MPS2, for measuring the macular pigment optical density of a Japanese population.

PURPOSE: The macular pigment optical density (MPOD) of a Japanese population was measured using a commercially based heterochromatic flicker photometer, the Macular Pigment Screener (MPS2). The objective of the study was to evaluate the accuracy and test-retest reliability of the MPS2 in Asian pigmented eyes. STUDY DESIGN: Experimental study to validate the medical instrument in humans. METHODS: Twenty-four healthy Japanese participants with no systemic or eye diseases (men: 13, women: 11; mean [SD] age 38.6 [10.9 years]) were included. The concordance of the MPOD, obtained using the MPS2 and Macular Metrics II (MM2), and the test-retest reliability were examined. RESULTS: Determination of the MPOD was unsuccessful in 1 participant; thus, the MPOD of 23 participants was analyzed. The mean (SD) MPOD measured with the detail-mode of the MPS2 was 0.63 (0.18) and with that of the MM2, it was 0.72 (0.23). The former was significantly lower than the latter (P = .003, paired t test). The MPOD measured with the MPS2 and the MM2 showed good concordance (r = 0.79, P < .001, Pearson product moment correlation). Bland-Altman analyses showed no systematic errors between the MPS2 and the MM2. The intraclass correlation coefficient over 5 measurement times with the detail-mode of the MPS2 was 0.80, and the mean coefficient of variation was 9.4%. CONCLUSION: The high concordance with the MM2 and good test-retest reliability found by this study suggest that the MPS2 is acceptable for use in a Japanese population. However, the mean MPOD yielded by the MPS2 was significantly lower than that yielded by the MM2. Therefore, the MPS2 and MM2 are not interchangeable in a single study.

Functional Analysis of the Yeast LINC Complex Using Fluctuation Spectroscopy and Super-Resolution Imaging.

The Saccharomyces cerevisiae and Schizosaccharomyces pombe genomes encode a single SUN domain-containing protein, Mps3 and Sad1, respectively. Both localize to the yeast centrosome (known as the spindle pole body, SPB) and are essential for bipolar spindle formation. In addition, Mps3 and Sad1 play roles in chromosome organization in both mitotic and meiotic cells that are independent of their SPB function. To dissect the function of Mps3 at the nuclear envelope (NE) and SPB, we employed cell imaging methods such as scanning fluorescence cross-correlation spectroscopy (SFCCS) and single particle averaging with structured illumination microscopy (SPA-SIM) to determine the strength, nature, and location of protein-protein interactions in vivo. We describe how these same techniques can also be used in fission yeast to analyze Sad1, providing evidence of their applicability to other NE proteins and systems.