Publications by authors named "Or Rotem"

Eye movements have long been recognized as a valuable indicator of neurological conditions, given the intricate involvement of multiple neurological pathways in vision-related processes, including motor and cognitive functions, manifesting in rapid response times. Eye movement abnormalities can indicate neurological condition severity and, in some cases, distinguish between disease phenotypes. With recent strides in imaging sensors and computational power, particularly in machine learning and artificial intelligence, there has been a notable surge in the development of technologies facilitating the extraction and analysis of eye movements to assess neurodegenerative diseases.

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Achieving seed germination quality standards poses a real challenge to seed companies as they are compelled to abide by strict certification rules, while having only partial seed separation solutions at their disposal. This discrepancy results with wasteful disqualification of seed lots holding considerable amounts of good seeds and further translates to financial losses and supply chain insecurity. Here, we present the first-ever generic germination prediction technology that is based on deep learning and RGB image data and facilitates seed classification by seed germinability and usability, two facets of germination fate.

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The small size of bacterial cells necessitates rapid adaption to sudden environmental changes. In Bdellovibrio bacteriovorus, an obligate predator of bacteria common in oligotrophic environments, the non-replicative, highly motile attack phase (AP) cell must invade a prey to ensure replication. AP cells swim fast and respire at high rates, rapidly consuming their own contents.

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Elevation of temperature is a frequent and considerable stress for mesophilic bacteria. Therefore, several molecular mechanisms have evolved to cope with high temperature. We have been studying the response of Agrobacterium tumefaciens to temperature stress, focusing on two aspects: the heat-shock response and the temperature-dependent regulation of methionine biosynthesis.

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Soil is a microenvironment with a fragmented (patchy) spatial structure in which many bacterial species interact. Here, we explore the interaction between the predatory bacterium Bdellovibrio bacteriovorus and its prey Escherichia coli in microfabricated landscapes. We ask how fragmentation influences the prey dynamics at the microscale and compare two landscape geometries: a patchy landscape and a continuous landscape.

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Cultured tomatoes are often exposed to a combination of extreme heat and infection with Tomato yellow leaf curl virus (TYLCV). This stress combination leads to intense disease symptoms and yield losses. The response of TYLCV-susceptible and resistant tomatoes to heat stress together with viral infection was compared.

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Tomato yellow leaf curl virus (TYLCV) is a begomovirus transmitted by the whitefly Bemisia tabaci to tomato and other crops. TYLCV proteins are endangered by the host defenses. We have analyzed the capacity of the tomato plant and of the whitefly insect vector to degrade the six proteins encoded by the TYLCV genome.

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Predators feed on prey to acquire the nutrients necessary to sustain their survival, growth, and replication. In Bdellovibrio bacteriovorus, an obligate predator of Gram-negative bacteria, cell growth and replication are tied to a shift from a motile, free-living phase of search and attack to a sessile, intracellular phase of growth and replication during which a single prey cell is consumed. Engagement and sustenance of growth are achieved through the sensing of two unidentified prey-derived cues.

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Unlabelled: Over the course of the last 3 decades the role of the second messenger cyclic di-GMP (c-di-GMP) as a master regulator of bacterial physiology was determined. Although the control over c-di-GMP levels via synthesis and breakdown and the allosteric regulation of c-di-GMP over receptor proteins (effectors) and riboswitches have been extensively studied, relatively few effectors have been identified and most are of unknown functions. The obligate predatory bacterium Bdellovibrio bacteriovorus has a peculiar dimorphic life cycle, in which a phenotypic transition from a free-living attack phase (AP) to a sessile, intracellular predatory growth phase (GP) is tightly regulated by specific c-di-GMP diguanylate cyclases.

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Bdellovibrio bacteriovorus is an obligate predator of bacteria ubiquitously found in the environment. Its life cycle is composed of two essential phases: a free-living, non-replicative, fast swimming attack phase (AP) wherein the predator searches for prey; and a non-motile, actively dividing growth phase (GP) in which it consumes the prey. The molecular regulatory mechanisms governing the switch between AP and GP are largely unknown.

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Predatory bacteria are taxonomically disparate, exhibit diverse predatory strategies and are widely distributed in varied environments. To date, their predatory phenotypes cannot be discerned in genome sequence data thereby limiting our understanding of bacterial predation, and of its impact in nature. Here, we define the 'predatome,' that is, sets of protein families that reflect the phenotypes of predatory bacteria.

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Here we characterize the first step in methionine biosynthesis in Agrobacterium tumefaciens, an α-proteobacterium. We explored the metA gene and its products and found several unique properties. Although the gene was annotated as a homoserine transsuccinylase, based upon sequence similarity to characterized homologs in other bacteria, including Escherichia coli, the enzyme uses acetyl-CoA as a substrate and therefore is functionally a transacetylase.

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