Phloem transport: Are you chaperoned?
نویسندگان
چکیده
Long-distance transport via the vasculature in plants is critical for nutrient dissemination, as well as transport of growth regulatory molecules such as hormones. Evidence is now accumulating that protein and RNA molecules also use this transport pathway, possibly to regulate developmental and physiological processes.
منابع مشابه
Phloem transport in trees.
Phloem is like an enigmatic central banker: we know how important phloem is to plant function, but very little about how phloem functions as part of a whole-plant economy. Phloem transports carbohydrates, produced by photosynthesis and hydrolysis of reserve compounds, to sink tissues for growth, respiration and storage. At photosynthetic tissues, carbohydrates are loaded into phloem (Rennie and...
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Substantial symplastic continuity appears to exist between companion cells (CCs) and sieve elements of the phloem, which suggests that small solutes within the CC are subject to indiscriminate long-distance transport via the translocation stream. To test this hypothesis, the distributions of exotic and endogenous solutes synthesized in the CCs of minor veins were studied. Octopine, a charged mo...
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عنوان ژورنال:
- Current Biology
دوره 9 شماره
صفحات -
تاریخ انتشار 1999