|
Descripción
|
|
|---|---|
| The phloem is known as the main conduit for assimilates synthesized during photosynthesis, but also spreads signals coordinating important developmental decisions and physiological responses between plant organs. Among the wealth of potential signaling molecules, RNAs have outstanding potential, because they allow the transmission of sequence-specific information. Moreover, especially small RNAs in the size range of 20?26 nucleotides are likely to be phloem-mobile due to their small size. While RNAs were found to be absent from xylem sap, sieve elements seem to be a suitable route for RNA transport, since phloem samples have been shown to be free of RNase activity that could compromise RNA quality. Recently, a large number of small RNAs including micro (mi) and short interfering (si) RNAs have been identified in phloem samples what fueled the speculation that they could be long-distance information transmitters. However, that they can really be translocated through the phloem in vivo could so far only been demonstrated for siRNAs and a small number of miRNAs. siRNA translocation is thought to be essential for the plant-wide transmission of silencing of aberrant endogenous, viral- or transgene-derived RNAs. In contrast, the three miRNAs for which phloem mobility could as yet be verified are involved in tuber development (miR172) or nutrient deprivation responses (miR395 and miR399). Future experiments will be required to show whether additional small RNAs with distinct functions can also travel through the phloem or not. | |
|
Internacional
|
Si |
|
DOI
|
|
|
Edición del Libro
|
|
|
Editorial del Libro
|
Kragler, Friedrich; Hülskamp, Martin (Eds.) Springer New York. |
|
ISBN
|
978-1-4419-1531-3 |
|
Serie
|
Short and Long Distance Signaling, vol. 3 |
|
Título del Libro
|
Advances in Plant Biology |
|
Desde página
|
131 |
|
Hasta página
|
149 |