Summary
The cannabis leaf is iconic, but it is the flowers of cannabis that are consumed for the psychoactive and medicinal effects of their specialized metabolites. Cannabinoid metabolites, together ...with terpenes, are produced in glandular trichomes. Superficially, stalked and sessile trichomes in cannabis only differ in size and whether they have a stalk. The objectives of this study were: to define each trichome type using patterns of autofluorescence and secretory cell numbers, to test the hypothesis that stalked trichomes develop from sessile‐like precursors, and to test whether metabolic specialization occurs in cannabis glandular trichomes. A two‐photon microscopy technique using glandular trichome intrinsic autofluorescence was developed which demonstrated that stalked glandular trichomes possessed blue autofluorescence correlated with high cannabinoid levels. These stalked trichomes had 12–16 secretory disc cells and strongly monoterpene‐dominant terpene profiles. In contrast, sessile trichomes on mature flowers and vegetative leaves possessed red‐shifted autofluorescence, eight secretory disc cells and less monoterpene‐dominant terpene profiles. Moreover, intrinsic autofluorescence patterns and disc cell numbers supported a developmental model where stalked trichomes develop from apparently sessile trichomes. Transcriptomes of isolated floral trichomes revealed strong expression of cannabinoid and terpene biosynthetic genes, as well as uncharacterized genes highly co‐expressed with CBDA synthase. Identification and characterization of two previously unknown and highly expressed monoterpene synthases highlighted the metabolic specialization of stalked trichomes for monoterpene production. These unique properties and highly expressed genes of cannabis trichomes determine the medicinal, psychoactive and sensory properties of cannabis products.
Significance Statement
The unique monoterpene‐rich cannabis stalked trichomes that determine the medicinal, psychoactive and sensory properties of cannabis flowers develop from sessile‐like intermediates.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
There have been few studies on quantifying carotenoid accumulation in carrots, and none have taken the comparative approach. The abundance and distribution of carotenes in carrot roots of three ...varieties, white, orange, and high carotene mass (HCM) were compared using light and transmission electron microscopy (TEM). Light microscopy has indicated that, in all three varieties, carotenes were most abundant in the secondary phloem and this area was selected for further TEM analysis. While carotenes were extracted during the fixation process for TEM, the high-pressure freezing technique we employed preserved the spaces (CS) left behind by the extracted carotene crystals. Chromoplasts from the HCM variety contained significantly (P < 0.05) more CS than chromoplasts from the orange variety. Chromoplasts from the white variety had few or no CS. There was no significant difference between the HCM and orange varieties in the number of chromoplasts per unit area, but the white variety had significantly (P < 0.05) fewer chromoplasts than the other two varieties. A large number of starch-filled amyloplasts was observed in secondary phloem of the white variety but these were not found in the other two varieties. The results from this comparative approach clearly define the subcellular localization of carotenoids in carrot roots and suggest that while the HCM genotype was selectively bred for increased carotene content, this selection did not lead to increased numbers of carotene-containing chromoplasts but rather greater accumulation of carotene per chromoplast. Furthermore, the results confirm that roots of the white carrot variety retain residual amounts of carotene.
Secondary xylem (wood) formation in gymnosperms requires that the tracheid protoplasts first build an elaborate secondary cell wall from an array of polysaccharides and then reinforce it with lignin, ...an amorphous, three-dimensional product of the random radical coupling of monolignols. The objective of this study was to track the spatial distribution of monolignols during development as they move from symplasm to apoplasm. This was done by feeding ³Hphenylalanine (³HPhe) to dissected cambium/developing wood from lodgepole pine (Pinus contorta var latifolia) seedlings, allowing uptake and metabolism, then rapidly freezing the cells and performing autoradiography to detect the locations of the monolignols responsible for lignification. Parallel experiments showed that radioactivity was incorporated into polymeric lignin and a methanol-soluble pool that was characterized by high-performance liquid chromatography. ³HPhe was incorporated into expected lignin precursors, such as coniferyl alcohol and p-coumaryl alcohol, as well as pinoresinol. Coniferin, the glucoside of coniferyl alcohol, was detected by high-performance liquid chromatography but was not radioactively labeled. With light microscopy, radiolabeled phenylpropanoids were detected in the rays as well as the tracheids, with the two cell types showing differential sensitivity to inhibitors of protein translation and phenylpropanoid metabolism. Secondary cell walls of developing tracheids were heavily labeled when incubated with ³HPhe. Inside the cell, cytoplasm was most strongly labeled followed by Golgi and low-vacuole label. Inhibitor studies suggest that the Golgi signal could be attributed to protein, rather than phenylpropanoid, origins. These data, produced with the best microscopy tools that are available today, support a model in which unknown membrane transporters, rather than Golgi vesicles, export monolignols.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Abstract Objectives To compare magnetic resonance imaging–targeted biopsy (MRITB) and conventional transrectal ultrasound–guided biopsy (TRUSGB) in the detection of prostate cancer (PCa) at our ...institution. Methods Our prospective registry of patients undergoing prostate MRITB from December 2010 to July 2013 was analyzed. Patients were matched one-to-one to patients who underwent TRUSGB based on the following characteristics: age, prostate-specific antigen level, prostate volume, race, family history of PCa, initial digital rectal examination (DRE), prior use of 5-alpha reductase inhibitor, and prior diagnosis of PCa. MRITB was performed using a TargetScan system with the patient under general anesthesia. Magnetic resonance imaging suspicious regions (MSRs) were targeted with cognitive registration, and a full TargetScan template biopsy (TSTB) was also performed. Results In total, 34 MRITB patients were matched individually to 34 TRUSGB patients. As compared with TRUSGB, patients who underwent MRITB had a greater overall rate of PCa detection (76% vs. 56%, P = 0.12) and a significantly higher number with Gleason score≥7 (41% vs. 15%, P = 0.03), whereas the rates of Gleason score 6 PCa detection were similar between MRITB and TRUSGB (35% vs. 41%, P = 0.80). As compared with the TSTB, magnetic resonance imaging suspicious regions–directed biopsies during MRITB had a significantly higher overall PCa detection (54% vs. 24%, P <0.01) and Gleason score≥7 PCa detection (25% vs. 8%, P <0.01). When compared with TSTB, TRUSGB had similar detection rates for benign prostate tissue (76% vs. 79%, P = 0.64), Gleason score 6 PCa (16% vs. 14%, P = 0.49), and Gleason score ≥7 PCa detection (8% vs. 7%, P = 1.0). Conclusions Cognitive registration MRITB significantly improves the detection of Gleason score≥7 PCa as compared with conventional TRUSGB.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Secondary xylem (wood) formation in gymnosperms requires that the tracheid protoplasts first build an elaborate secondary cell wall from an array of polysaccharides and then reinforce it with lignin, ...an amorphous, three-dimensional product of the random radical coupling of monolignols. The objective of this study was to track the spatial distribution of monolignols during development as they move from symplasm to apoplasm. This was done by feeding (3)Hphenylalanine ((3)HPhe) to dissected cambium/developing wood from lodgepole pine (Pinus contorta var latifolia) seedlings, allowing uptake and metabolism, then rapidly freezing the cells and performing autoradiography to detect the locations of the monolignols responsible for lignification. Parallel experiments showed that radioactivity was incorporated into polymeric lignin and a methanol-soluble pool that was characterized by high-performance liquid chromatography. (3)HPhe was incorporated into expected lignin precursors, such as coniferyl alcohol and p-coumaryl alcohol, as well as pinoresinol. Coniferin, the glucoside of coniferyl alcohol, was detected by high-performance liquid chromatography but was not radioactively labeled. With light microscopy, radiolabeled phenylpropanoids were detected in the rays as well as the tracheids, with the two cell types showing differential sensitivity to inhibitors of protein translation and phenylpropanoid metabolism. Secondary cell walls of developing tracheids were heavily labeled when incubated with (3)HPhe. Inside the cell, cytoplasm was most strongly labeled followed by Golgi and low-vacuole label. Inhibitor studies suggest that the Golgi signal could be attributed to protein, rather than phenylpropanoid, origins. These data, produced with the best microscopy tools that are available today, support a model in which unknown membrane transporters, rather than Golgi vesicles, export monolignols.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Sacci of conifer pollen do not function primarily to increase the efficiency of wind pollination as is widely thought. Rather, they are bladders and cause pollen to float upwards in a liquid drop ...into the ovules. This observation is seemingly unsupported in the case of oriental spruce (Picea orientalis (L.) Link), which has saccate pollen. Ovulate cones are pendant at the time of pollination, which requires that pollen sink into the ovules. Pollen of oriental spruce floats at first but within 1-2 min sinks into the ovule. As sinking does not occur in saccate pollen of other Pinaceae, a variety of techniques was used to determine anatomical differences leading to this uncharacteristic tendency. Light, scanning electron, and confocal microscopy of the pollen surface yielded no significant appearing difference between pollen of oriental spruce and white spruce. However, transmission electron microscopy of freeze-fixed/freeze-substituted hydrated pollen revealed that the ektexine of oriental spruce pollen sacci is porous compared to that of white spruce. Confocal microscopy allowed examination of pollen hydration dynamics. Water enters pollen at the distal pole between sacci, and resulting rapid expansion of the tube cell forces air out of the saccate space. White spruce pollen remains buoyant because of enclosed air pockets in the saccus ektexine. Evolutionary change in pollen wall anatomy with resultant loss of saccus function is correlated with a change in ovulate strobilus orientation at pollination in oriental spruce. A suite of characters interact in the conifer pollination mechanism, and concerted change in these characters may lead to speciation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Habituation of wild great apes for tourism and research has had a significant positive effect on the conservation of these species. However, risks associated with such activities have been ...identified, specifically the transmission of human respiratory viruses to wild great apes, causing high morbidity and, occasionally, mortality. Here, we investigate the source of bacterial-viral co-infections in wild and captive chimpanzee communities in the course of several respiratory disease outbreaks. Molecular analyses showed that human respiratory syncytial viruses (HRSV) and human metapneumoviruses (HMPV) were involved in the etiology of the disease. In addition our analysis provide evidence for coinfection with Streptococcus (S.) pneumoniae. Characterisation of isolates from wild chimpanzees point towards a human origin of these bacteria. Transmission of these bacteria is of concern because - in contrast to HRSV and HMPV - S. pneumoniae can become part of the nasopharyngeal flora, contributing to the severity of respiratory disease progression. Furthermore these bacteria have the potential to spread to other individuals in the community and ultimately into the population. Targeted vaccination programs could be used to vaccinate habituated great apes but also human populations around great ape habitats, bringing health benefits to both humans and wild great apes.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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