Ever since plants colonized land, they evolved mechanisms to respond to changing environmental conditions and settle in extreme habitats. Recent studies show that several plant species require microbial associations for stress tolerance and survival. Although many plants lack the adaptive capability to adapt to stress conditions, the ability of a variety of plants to adapt to stress conditions often appears to depend on their association with certain microbes, raising a number of questions: What distinguishes the microbes and plants that can adapt to extreme environmental conditions? Can all plants improve stress tolerance when associated with appropriate microbial partners? Answers to these questions should modify our concepts of plant physiology and could lead to new ways towards a sustainable agriculture.

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Plants adapt to the environment by either long-term genome evolution or by acclimatization processes where the cellular processes and metabolism of the plant are adjusted within the existing potential in the genome. Here we studied the adaptation strategies in date palm, Phoenix dactylifera, under mild heat, drought and combined heat and drought by transcriptomic and metabolomic profiling. In transcriptomics data, combined heat and drought resembled heat response, whereas in metabolomics data it was more similar to drought. In both conditions, soluble carbohydrates, such as fucose, and glucose derivatives, were increased, suggesting a switch to carbohydrate metabolism and cell wall biogenesis. This result is consistent with the evidence from transcriptomics and cis-motif analysis. In addition, transcriptomics data showed transcriptional activation of genes related to reactive oxygen species in all three conditions (drought, heat, and combined heat and drought), suggesting increased activity of enzymatic antioxidant systems in cytosol, chloroplast and peroxisome. Finally, the genes that were differentially expressed in heat and combined heat and drought stresses were significantly enriched for circadian and diurnal rhythm motifs, suggesting new stress avoidance strategies.

Background: Camel production in Saudi Arabia is severely affected by various diseases and by inadequate veterinary services. Ticks and tick-borne pathogens (TBPs) affect the health and wellbeing of camels consequently diminishing their productivity and performances. In addition, camels may act as hosts for TBPs (e.g. Anaplasma phagocytophilum) causing diseases in humans. The current study aimed to determine the prevalence of ixodid ticks and molecularly investigate the associated pathogens in camels from Saudi Arabia. Methods: Blood and tick samples were collected from camels (n = 170) in Riyad Province of Saudi Arabia. Ticks were morphologically identified, and blood of camels were molecularly screened for apicomplexan (i.e. Babesia spp., Theileria spp., Hepatozoon spp.) and rickettsial parasites (i.e. Ehrlichia spp. and Anaplasma spp.). Results: Of the 170 camels examined, 116 (68.2%; 95% CI: 60.9-75.1%) were infested by ticks with a mean intensity of 2.53 (95% CI: 2.4-2.6). In total of 296 ticks collected, Hyalomma dromedarii was the most prevalent (76.4%), followed by Hyalomma impeltatum (23.3%) and Hyalomma excavatum (0.3%). Of the tested animals, 13 (7.6%; 95% CI: 4.3-12.8%) scored positive to at least one TBP, with Anaplasma platys (5.3%; 95% CI: 2.7-9.9%) being the most prevalent species, followed by Anaplasma phagocytophilum, Anaplasma sp., Ehrlichia canis and Hepatozoon canis (0.6% each; 95% CI: 0.04-3.4%). None of the camels were found to be co-infected with more than one pathogen. All samples tested negative for Babesia spp. and Theileria spp. Conclusions: The present study reveals the occurrence of different tick species and TBPs in camels from Saudi Arabia. Importantly, these camels may carry A. phagocytophilum and A. platys, representing a potential risk to humans.

AGC kinases are important regulators of cell growth, metabolism, division, and survival in mammalian systems. Mutation or deregulation of members of this family of protein kinases contribute to the pathogenesis of many human diseases, including cancer and diabetes. Although AGC kinases are conserved in the plant kingdom, little is known about their molecular functions and targets. Some of the best-studied plant AGC kinases mediate auxin signaling and are thereby involved in the regulation of growth and morphogenesis. Furthermore, certain members are regulated by lipid-derived signals via the 3-phosphoinositide-dependent kinase 1 (PDK1) and the kinase target of rapamycin (TOR), similar to its animal counterparts. In this review, we discuss recent findings on plant AGC kinases that unravel important roles in the regulation of plant growth, immunity and cell death, and connections to stress-induced mitogen-activated protein kinase signaling cascades.

Despite the global distribution of the brown dog tick, Rhipicephalus sanguineus (Latreille, 1806) sensu lato (s.l.), limited information exists about their identity from the Arabian Peninsula. Ticks from free roaming urban dogs and dromedary camels in Riyadh, Saudi Arabia were morphologically identified, confirmed with scanning electron microscopy and characterised at mitochondrial DNA (cox1, 12S rDNA and 16S rDNA). A total of 186 ticks were collected from 65 free roaming dogs (n = 73) and 84 dromedary camels (n = 113). Morphologically, 5.9% (11/186) were R. sanguineus s.l. and Hyalomma spp. (93.5%, 174/186). From within R. sanguineus s.l., the presence of Rhipicephalus cf. camicasi Morel, Mouchet et Rodhain, 1976 (1 dog, 2 camels) and Rhipicephalus turanicus Pomerantsev, 1936 (1 camel) is reported. The examined R. cf. camicasi form a sister group to R. sanguineus s.l. tropical lineage at all DNA markers. Dogs were parasitised by Hyalomma dromedarii Koch, 1844 (n = 59), Hyalomma impeltatum Schulze et Schlottke, 1930 (n = 1), Hyalomma excavatum Koch, 1844 (n = 2), Hyalomma turanicum Pomerantsev, 1946 (n = 1) and Hyalomma rufipes Koch,1844 (n = 1). DNA from dog blood (n = 53) from Riyadh confirmed a low prevalence of canine vector-borne pathogens that does not exceed 5.7% for Babesia spp., Mycoplasma spp., Anaplasma platys, Hepatozoon canis and Ehrlichia canis using multiplexed tandem PCR (MT-PCR) and diagnostic PCR. Low prevalence of R. sanguineus s.l. on dogs likely contributed to the low level of canine vector-borne pathogens in Saudi Arabia. We demonstrate that dogs in the central Arabian Peninsula are more commonly parasitised by Hyalomma spp. than R. sanguineus s.l.

The current study was carried out to evaluate the ameliorative effect of fucoidan against aflatoxicosis-induced hepatorenal toxicity in streptozotocin-induced diabetic rats. Sixty-four Wister albino male rats were randomly assigned into eight groups (8 rats each) that received normal saline, fucoidan (FUC) at 100 mg/kg/day orally for 4 weeks, streptozotocin (STZ) at 50 mg/kg/i.p. single dose, STZ plus FUC, aflatoxin B 1 (AFB 1 ) at 50 μg/kg/i.p. after one month of the beginning of the experiment for 2 weeks, AFB 1 plus FUC, STZ plus AFB 1 , or STZ plus AFB 1 and FUC. Injection of rats with STZ induced hyperglycemia. Rats with STZ-induced diabetes, with or without AFB 1 intoxication, had significantly elevated activities of serum aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase, and levels of serum urea, creatinine, cholesterol, 8-oxo-2′-deoxyguanosine, interleukin-1β, interleukin-6, and tumor necrosis factor-α. In addition, these rats exhibited increased lipid peroxidation and reduced glutathione concentration and activities of superoxide dismutase, catalase, and glutathione peroxidase enzymes in the hepatic and renal tissues. In contrast, administration of FUC to diabetic rats, with or without AFB 1 intoxication, ameliorated the altered serum parameters, reduced oxidative stress, DNA damage, and inflammatory biomarkers, and enhanced the antioxidant defense system in the hepatic and renal tissues. These results indicated that FUC ameliorated diabetes and AFB 1 -induced hepatorenal injuries through alleviating oxidative stress, DNA damage, and inflammation.

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